2005, 日本気象学会, 堀内賞　　　　　　　　　　　　　　　
地球および惑星における主要親気性元素の挙動に関する理論的研究
倉本 圭, Japan

2005, 2005, Horiuchi Prize, Meteorological Society of Japan　　　　　　　　　　　　　　　

Suppression of hydrodynamic escape of an H2-rich early Earth atmosphere by radiative cooling of carbon oxides
Tatsuya Yoshida, Naoki Terada, Kiyoshi Kuramoto
Progress in Earth and Planetary Science, 11, 1, Springer Science and Business Media LLC, 21 Nov. 2024
Scientific journal, Abstract

Radiative cooling by molecules is a crucial process for hydrodynamic escape, as it can efficiently remove the thermal energy driving the outflow, acquired through X-ray and extreme UV absorption. Carbon oxides, such as CO and CO₂, and their photochemical products are anticipated to serve as vital radiative cooling sources not only in atmospheres dominated by carbon oxides but also in H₂-rich atmospheres. However, their specific effects on the hydrodynamic escape, especially in H₂-rich atmospheres, have been inadequately investigated. In this study, we conduct 1-D hydrodynamic escape simulations for H₂-rich atmospheres incorporating CO, CO₂, and their chemical products on an Earth-mass planet. We consider detailed radiative cooling processes and chemical networks related to carbon oxides to elucidate their impacts on the hydrodynamic escape. In the escape outflow, CO₂ undergoes rapid photolysis, producing CO and atomic oxygen, while CO exhibits photochemical stability compared to CO₂. The H₂ oxidation by atomic oxygen results in the production of OH and H₂O. Consequently, the hydrodynamic escape is significantly suppressed by the radiative cooling effects of CO, H₂O, OH, and H₃⁺ even when the basal mixing fraction of CO and CO₂ is lower than ~ 0.01. These mechanisms extend the lifetime of H₂-rich atmospheres by about one order of magnitude compared to the case of pure hydrogen atmospheres on early Earth, which also results in negligible escape of heavier carbon- and nitrogen-bearing molecules and noble gases.

Self-Shielding Enhanced Organics Synthesis in an Early Reduced Earth’s Atmosphere
Tatsuya Yoshida, Shungo Koyama, Yuki Nakamura, Naoki Terada, Kiyoshi Kuramoto
Astrobiology, Mary Ann Liebert Inc, 22 Oct. 2024
Scientific journal

Study of hydrated asteroids via their polarimetric properties at low phase angles
Jooyeon Geem, Masateru Ishiguro, Hiroyuki Naito, Sunao Hasegawa, Jun Takahashi, Yoonsoo P. Bach, Sunho Jin, Seiko Takagi, Tatsuharu Ono, Daisuke Kuroda, Tomohiko Sekiguchi, Kiyoshi Kuramoto, Tomoki Nakamura, Makoto Watanabe
Astronomy & Astrophysics, 688, A195, A195, EDP Sciences, 22 Aug. 2024
Scientific journal, Context. Ch-type asteroids are distinctive among other dark asteroids in that they exhibit deep negative polarization branches (NPBs). Nevertheless, the physical and compositional properties that cause their polarimetric distinctiveness are less investigated.

Aims. We aim to investigate the polarimetric uniqueness of Ch-type asteroids by making databases of various observational quantities (i.e., spectroscopic and photometric properties as well as polarimetric ones) of dark asteroids.

Methods. We conducted an intensive polarimetric survey of 52 dark asteroids (including 31 Ch-type asteroids) in the R_C band to increase the size of polarimetric samples. The observed data were compiled with previous polarimetric, spectroscopic, and photometric archival data to find their correlations.

Results. We find remarkable correlations between these observed quantities, particularly the depth of NPBs and their spectroscopic features associated with the hydrated minerals. The amplitude of the opposition effect in photometric properties also shows correlations with polarimetric and spectral properties. However, these observed quantities do not show noticeable correlations with the geometric albedo, thermal inertia, and diameter of asteroids.

Conclusions. Based on the observational evidence, we arrive at our conclusion that the submicrometer-sized structures (fibrous or flaky puff pastry-like structures in phyllosilicates) in the regolith particles could contribute to the distinctive NPBs of hydrated asteroids.

Volatile mass partitioned among atmosphere, mantle, and core in proto-Mars
Hiroaki Saito, Kiyoshi Kuramoto
The Astrophysical Journal, 969, 158, 1, 9, 10 Jul. 2024, [Peer-reviewed]
English, Scientific journal

Origin of Phobos and Deimos Awaiting Direct Exploration
Kiyoshi Kuramoto
Annual Review of Earth and Planetary Sciences, 52, 1, Annual Reviews, 15 Feb. 2024, [Peer-reviewed], [Invited], [Lead author]
English, Scientific journal, Two major hypotheses have been proposed for the origin of the Martian moons Phobos and Deimos: the in situ formation theory, supported by the fact that they have circular orbits nearly parallel to the Martian equator, and the asteroid capture theory, supported by the similarity of their reflectance spectra to those of carbonaceous asteroids. Regarding the in situ formation theory, recent theoretical studies have focused on the huge impact scenario, which proposes that debris ejected into orbits during the formation of a giant impact basin on Mars accumulated to form the Martian moons. On the other hand, gas drag from a Martian gas envelope composed of gravitationally attracted solar nebula gas has been proposed as a mechanism for trapping the approaching asteroidal objects in areocentric orbits. In particular, an object entering a temporarily captured orbit in the Martian gravitational sphere would easily evolve into a fully captured moon with a near-equatorial orbit under realistic gas densities. The upcoming Phobos sample return mission is expected to elucidate the origin of both moons, with implications for material transport in the early Solar System and the early evolution of Mars. ▪ The origin of Mars’ small moons, Phobos and Deimos, has long been an open question. ▪ The leading hypotheses are asteroid capture, inferred from their appearance like primitive asteroids, and giant impact, implied by the regularity of their orbits. ▪ The origin of Phobos will be precisely determined by a sample return mission to be conducted in the late 2020s to early 2030s. ▪ Determining the origin of the Martian moons will provide clues to clarifying how the parent planet Mars formed and came to have a habitable surface environment.

Expected final online publication date for the Annual Review of Earth and Planetary Sciences, Volume 52 is May 2024. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Curation protocol of Phobos sample returned by Martian Moons eXploration
Ryota Fukai, Tomohiro Usui, Wataru Fujiya, Yoshinori Takano, Ken‐ichi Bajo, Andrew Beck, Enrica Bonato, Nancy L. Chabot, Yoshihiro Furukawa, Hidenori Genda, Yuki Hibiya, Fred Jourdan, Thorsten Kleine, Mizuho Koike, Moe Matsuoka, Yayoi N. Miura, Frédéric Moynier, Ryuji Okazaki, Sara S. Russell, Hirochika Sumino, Michael E. Zolensky, Haruna Sugahara, Shogo Tachibana, Kanako Sakamoto, Masanao Abe, Yuichiro Cho, Kiyoshi Kuramoto
Meteoritics & Planetary Science, Wiley, 11 Jan. 2024, [Peer-reviewed]
Scientific journal, Abstract

Japan Aerospace Exploration Agency's Martian Moons eXploration (MMX) mission will launch a spacecraft in 2024 to return samples from Phobos in 2029. Curatorial work for the returned Phobos samples is critical for the sample allocation without degrading the sample integrity and subsequent sample analysis that will provide new constraints on the origin of Phobos and the evolution of the circum‐Mars environment. The Sample Analysis Working Team of the MMX is designing the sample curation protocol. The curation protocol consists of three phases: (1) quick analysis (extraction and mass spectrometry for gases), (2) pre‐basic characterization (bulk‐scale observation), and (3) basic characterization (grain‐by‐grain observation and allocation of the sample aliquots). Nondestructive analyses within the clean chamber (e.g., visible and near‐infrared spectral imaging) and outside the chamber (e.g., gas mass spectrometry) are incorporated into the curation flow in coordination with the MMX mission instrument teams for ground‐truthing the remote‐sensing data sets. The MMX curation/sample analysis flow enables the seamless integration between the sample and remote‐sensing data sets to maximize the scientific value of the collected Phobos samples.

Radiative Effects on the Formation of the Stably Stratified Layer in the Lower Atmosphere of Venus
Yoshiyuki O. TAKAHASHI, Yoshi-Yuki HAYASHI, George L. HASHIMOTO, Kiyoshi KURAMOTO, Masaki ISHIWATARI, Hiroki KASHIMURA
Journal of the Meteorological Society of Japan. Ser. II, 102, 5, 469, 483, Meteorological Society of Japan, 2024
Scientific journal

Dependence of the Radiative-Convective Equilibrium Structure of the Lower Atmosphere of Venus on the Thermodynamic Model
Yoshiyuki O. TAKAHASHI, Yoshi-Yuki HAYASHI, George L. HASHIMOTO, Kiyoshi KURAMOTO, Masaki ISHIWATARI, Hiroki KASHIMURA
Journal of the Meteorological Society of Japan. Ser. II, 102, 1, 5, 16, Meteorological Society of Japan, 2024
Scientific journal

Development of a Line-by-line and a Correlated k-distribution Radiation Models for Planetary Atmospheres
Yoshiyuki O. TAKAHASHI, Yoshi-Yuki HAYASHI, George L. HASHIMOTO, Kiyoshi KURAMOTO, Masaki ISHIWATARI
Journal of the Meteorological Society of Japan. Ser. II, Meteorological Society of Japan, 2023, [Peer-reviewed]
English, Scientific journal

Preliminary design of Martian Moons eXploration (MMX)
Yasuhiro Kawakatsu, Kiyoshi Kuramoto, Tomohiro Usui, Haruna Sugahara, Hisashi Ootake, Ryoichiro Yasumitsu, Kent Yoshikawa, Stephane Mary, Markus Grebenstein, Hirotaka Sawada, Takane Imada, Takanobu Shimada, Kazunori Ogawa, Masatsugu Otsuki, Mitsuhisa Baba, Kazuhisa Fujita, Kris Zacny, Dylan van Dyne, Yasutaka Satoh, Ayumu Tokaji
Acta Astronautica, 202, 715, 728, Elsevier BV, Oct. 2022
Scientific journal

Less Effective Hydrodynamic Escape of H₂–H₂O Atmospheres on Terrestrial Planets Orbiting Pre-main-sequence M Dwarfs
Tatsuya Yoshida, Naoki Terada, Masahiro Ikoma, Kiyoshi Kuramoto
The Astrophysical Journal, 934, 2, 137, 137, American Astronomical Society, 01 Aug. 2022, [Peer-reviewed], [Last author]
English, Scientific journal, Abstract

Terrestrial planets currently in the habitable zones around M dwarfs likely experienced a long-term runaway-greenhouse condition because of a slow decline in host-star luminosity in its pre-main-sequence phase. Accordingly, they might have lost significant portions of their atmospheres including water vapor at high concentration by hydrodynamic escape induced by the strong stellar X-ray and extreme ultraviolet (XUV) irradiation. However, the atmospheric escape rates remain highly uncertain due partly to a lack of understanding of the effect of radiative cooling in the escape outflows. Here we carry out 1D hydrodynamic escape simulations for an H₂–H₂O atmosphere on a planet with mass of 1M_⊕ considering radiative and chemical processes to estimate the atmospheric escape rate and follow the atmospheric evolution during the early runaway-greenhouse phase. We find that the atmospheric escape rate decreases with the basal H₂O/H₂ ratio due to the energy loss by the radiative cooling of H₂O and chemical products such as OH and OH⁺: the escape rate of H₂ becomes one order of magnitude smaller when the basal H₂O/H₂ = 0.1 than that of the pure hydrogen atmosphere. The timescale for H₂ escape exceeds the duration of the early runaway-greenhouse phase, depending on the initial atmospheric amount and composition, indicating that H₂ and H₂O could be left behind after the end of the runaway-greenhouse phase. Our results suggest that temperate and reducing environments with oceans could be formed on some terrestrial planets around M dwarfs.

The Ganymede Laser Altimeter (GALA) for the Jupiter Icy Moons Explorer (JUICE): Mission, science, and instrumentation of its receiver modules
Keigo Enya, Masanori Kobayashi, Jun Kimura, Hiroshi Araki, Noriyuki Namiki, Hirotomo Noda, Shingo Kashima, Shoko Oshigami, Ko Ishibashi, T. Yamawaki, Kazuyuki Tohara, Yoshifumi Saito, Masanobu Ozaki, Takahide Mizuno, Shunichi Kamata, Koji Matsumoto, Sho Sasaki, Kiyoshi Kuramoto, Yuki Sato, Takeshi Yokozawa, Tsutomu Numata, Satoko Mizumoto, Hiroyuki Mizuno, Kenta Nagamine, Akihiko Sawamura, Kazuo Tanimoto, Hisato Imai, Hiroyuki Nakagawa, Okiharu Kirino, David Green, Masayuki Fujii, Satoru Iwamura, Naofumi Fujishiro, Yoshiaki Matsumoto, Kay Lingenauber, Reinald Kallenbach, Christian Althaus, Thomas Behnke, Jan Binger, Anna Daurskikh, Henri Eisenmenger, Ulrich Heer, Christian Hüttig, Luisa M. Lara, Alexander Lichopoj, Horst Georg Lötzke, Fabian Lüdicke, Harald Michaelis, Juan Pablo Rodriguez Garcia, Kerstin Rösner, Alexander Stark, Gregor Steinbrügge, Pascal Thabaut, Nicolas Thomas, Simone del Togno, Daniel Wahl, Belinda Wendler, Kai Wickhusen, Konrad Willner, Hauke Hussmann
Advances in Space Research, 69, 5, 2283, 2304, 01 Mar. 2022, [Peer-reviewed]
English, Scientific journal, The Jupiter Icy Moons Explorer (JUICE) is a science mission led by the European Space Agency, being developed for launch in 2023. The Ganymede Laser Altimeter (GALA) is an instrument onboard JUICE, whose main scientific goals are to understand ice tectonics based on topographic data, the subsurface structure by measuring tidal response, and small-scale roughness and albedo of the surface. In addition, from the perspective of astrobiology, it is imperative to study the subsurface ocean scientifically. The development of GALA has proceeded through an international collaboration between Germany (the lead), Japan, Switzerland, and Spain. Within this framework, the Japanese team (GALA-J) is responsible for developing three receiver modules: the Backend Optics (BEO), the Focal Plane Assembly (FPA), and the Analog Electronics Module (AEM). Like the German team, GALA-J also developed software to simulate the performance of the entire GALA system (performance model). In July 2020, the Proto-Flight Models of BEO, FPA, and AEM were delivered from Japan to Germany. This paper presents an overview of JUICE/GALA and its scientific objectives and describes the instrumentation, mainly focusing on Japan's contribution.

A polarimetric study of asteroids in comet-like orbits
Jooyeon Geem, Masateru Ishiguro, Yoonsoo P. Bach, Daisuke Kuroda, Hiroyuki Naito, Hidekazu Hanayama, Yoonyoung Kim, Yuna G. Kwon, Sunho Jin, Tomohiko Sekiguchi, Ryo Okazaki, Jeremie J. Vaubaillon, Masataka Imai, Tatsuharu Oono, Yuki Futamura, Seiko Takagi, Mitsuteru Sato, Kiyoshi Kuramoto, Makoto Watanabe
Astronomy and Astrophysics, 658, 01 Feb. 2022, [Peer-reviewed]
English, Scientific journal, Context. Asteroids in comet-like orbits (ACOs) consist of asteroids and dormant comets. Due to their similar appearance, it is challenging to distinguish dormant comets from ACOs via general telescopic observations. Surveys for discriminating dormant comets from the ACO population have been conducted via spectroscopy or optical and mid-infrared photometry. However, they have not been conducted through polarimetry. Aims. We conducted the first polarimetric research of ACOs. Methods. We conducted a linear polarimetric pilot survey for three ACOs: (944) Hidalgo, (3552) Don Quixote, and (331471) 1984 QY1. These objects are unambiguously classified into ACOs in terms of their orbital elements (i.e., the Tisserand parameters with respect to Jupiter TJ significantly less than 3). Three ACOs were observed by the 1.6 m Pirka Telescope from UT 2016 May 25 to UT 2019 July 22 (13 nights). Results. We found that Don Quixote and Hidalgo have polarimetric properties similar to comet nuclei and D-type asteroids (optical analogs of comet nuclei). However, 1984 QY1 exhibited a polarimetric property consistent with S-type asteroids. We conducted a backward orbital integration to determine the origin of 1984 QY1, and found that this object was transported from the main belt into the current comet-like orbit via the 3:1 mean motion resonance with Jupiter. Conclusions. We conclude that the origins of ACOs can be more reliably identified by adding polarimetric data to the color and spectral information. This study would be valuable for investigating how the ice-bearing small bodies distribute in the inner Solar System.

Polarimetric properties of the near-Sun asteroid (155140) 2005 UD in comparison with other asteroids and meteoritic samples
Masateru Ishiguro, Yoonsoo P. Bach, Jooyeon Geem, Hiroyuki Naito, Daisuke Kuroda, Myungshin Im, Myung Gyoon Lee, Jinguk Seo, Sunho Jin, Yuna G. Kwon, Tatsuharu Oono, Seiko Takagi, Mitsuteru Sato, Kiyoshi Kuramoto, Takashi Ito, Sunao Hasegawa, Fumi Yoshida, Tomoko Arai, Hiroshi Akitaya, Tomohiko Sekiguchi, Ryo Okazaki, Masataka Imai, Katsuhito Ohtsuka, Makoto Watanabe, Jun Takahashi, Maxime Devogèle, Grigori Fedorets, Lauri Siltala, Mikael Granvik
Monthly Notices of the Royal Astronomical Society, 509, 3, 4128, 4142, 01 Jan. 2022, [Peer-reviewed]
English, Scientific journal, The investigation of asteroids near the Sun is important for understanding the final evolutionary stage of primitive Solar system objects. A near-Sun asteroid (NSA), (155140) 2005 UD, has orbital elements similar to those of (3200) Phaethon (the target asteroid for the JAXA's DESTINY+ mission). We conducted photometric and polarimetric observations of 2005 UD and found that this asteroid exhibits a polarization phase curve similar to that of Phaethon over a wide range of observed solar phase angles (α = 20-105°) but different from those of (101955) Bennu and (162173) Ryugu (asteroids composed of hydrated carbonaceous materials). At a low phase angle (α 30°), the polarimetric properties of these NSAs (2005 UD and Phaethon) are consistent with anhydrous carbonaceous chondrites, while the properties of Bennu are consistent with hydrous carbonaceous chondrites. We derived the geometric albedo, pV ∼0.1 (in the range of 0.088-0.109); mean V-band absolute magnitude, HV = 17.54 ± 0.02; synodic rotational period, $T_mathrm{rot} = 5.2388 pm 0.0022 , mathrm{h}$ (the two-peaked solution is assumed); and effective mean diameter, $D_mathrm{eff} = 1.32 pm 0.06 , mathrm{km}$. At large phase angles (α 80°), the polarization phase curve are likely explained by the dominance of large grains and the paucity of small micron-sized grains. We conclude that the polarimetric similarity of these NSAs can be attributed to the intense solar heating of carbonaceous materials around their perihelia, where large anhydrous particles with small porosity could be produced by sintering.

The MMX rover: performing in situ surface investigations on Phobos
Patrick Michel, Stephan Ulamec, Ute Boettger, Matthias Grott, Naomi Murdoch, Pierre Vernazza, Cecily Sunday, Yun Zhang, Rudy Valette, Romain Castellani, Jens Biele, Simon Tardivel, Olivier Groussin, Laurent Jorda, Joerg Knollenberg, Jan Thimo Grundmann, Denis Arrat, Gabriel Pont, Stephane Mary, Markus Grebenstein, Hirdy Miyamoto, Tomoki Nakamura, Koji Wada, Kent Yoshikawa, Kiyoshi Kuramoto
EARTH PLANETS AND SPACE, 74, 1, SPRINGER, Jan. 2022, [Peer-reviewed]
English, Scientific journal, The Japanese MMX sample return mission to Phobos by JAXA will carry a rover developed by CNES and DLR that will be deployed on Phobos to perform in situ analysis of the Martian moon's surface properties. Past images of the surface of Phobos show that it is covered by a layer of regolith. However, the mechanical and compositional properties of this regolith are poorly constrained. In particular, from current remote images, very little is known regarding the particle sizes, their chemical composition, the packing density of the regolith as well as other parameters such as friction and cohesion that influence surface dynamics. Understanding the properties and dynamics of the regolith in the low-gravity environment of Phobos is important to trace back its history and surface evolution. Moreover, this information is also important to support the interpretation of data obtained by instruments onboard the main MMX spacecraft, and to minimize the risks involved in the spacecraft sampling operations. The instruments onboard the Rover are a Raman spectrometer (RAX), an infrared radiometer (miniRad), two forward-looking cameras for navigation and science purposes (NavCams), and two cameras observing the interactions of regolith and the rover wheels (WheelCams). The Rover will be deployed before the MMX spacecraft samples Phobos' surface and will be the first rover to drive on the surface of a Martian moon and in a very low gravity environment.

Martian moons exploration MMX: sample return mission to Phobos elucidating formation processes of habitable planets
Kiyoshi Kuramoto, Yasuhiro Kawakatsu, Masaki Fujimoto, Akito Araya, Maria Antonietta Barucci, Hidenori Genda, Naru Hirata, Hitoshi Ikeda, Takeshi Imamura, Jörn Helbert, Shingo Kameda, Masanori Kobayashi, Hiroki Kusano, David J. Lawrence, Koji Matsumoto, Patrick Michel, Hideaki Miyamoto, Tomokatsu Morota, Hiromu Nakagawa, Tomoki Nakamura, Kazunori Ogawa, Hisashi Otake, Masanobu Ozaki, Sara Russell, Sho Sasaki, Hirotaka Sawada, Hiroki Senshu, Shogo Tachibana, Naoki Terada, Stephan Ulamec, Tomohiro Usui, Koji Wada, Sei-ichiro Watanabe, Shoichiro Yokota
Earth, Planets and Space, 74, 1, SPRINGER, Jan. 2022, [Peer-reviewed], [Invited]
English, Scientific journal, Martian moons exploration, MMX, is the new sample return mission planned by the Japan Aerospace Exploration Agency (JAXA) targeting the two Martian moons with the scheduled launch in 2024 and return to the Earth in 2029. The major scientific objectives of this mission are to determine the origin of Phobos and Deimos, to elucidate the early Solar System evolution in terms of volatile delivery across the snow line to the terrestrial planets having habitable surface environments, and to explore the evolutionary processes of both moons and Mars surface environment. To achieve these objectives, during a stay in circum-Martian space over about 3 years MMX will collect samples from Phobos along with close-up observations of this inner moon and carry out multiple flybys of Deimos to make comparative observations of this outer moon. Simultaneously, successive observations of the Martian atmosphere will also be made by utilizing the advantage of quasi-equatorial spacecraft orbits along the moons' orbits.

Science operation plan of Phobos and Deimos from the MMX spacecraft
Tomoki Nakamura, Hitoshi Ikeda, Toru Kouyama, Hiromu Nakagawa, Hiroki Kusano, Hiroki Senshu, Shingo Kameda, Koji Matsumoto, Ferran Gonzalez-Franquesa, Naoya Ozaki, Yosuke Takeo, Nicola Baresi, Yusuke Oki, David J. Lawrence, Nancy L. Chabot, Patrick N. Peplowski, Maria Antonietta Barucci, Eric Sawyer, Shoichiro Yokota, Naoki Terada, Stephan Ulamec, Patrick Michel, Masanori Kobayashi, Sho Sasaki, Naru Hirata, Koji Wada, Hideaki Miyamoto, Takeshi Imamura, Naoko Ogawa, Kazunori Ogawa, Takahiro Iwata, Takane Imada, Hisashi Otake, Elisabet Canalias, Laurence Lorda, Simon Tardivel, Stephane Mary, Makoto Kunugi, Seiji Mitsuhashi, Alain Doressoundiram, Frederic Merlin, Sonia Fornasier, Jean-Michel Reess, Pernelle Bernardi, Shigeru Imai, Yasuyuki Ito, Hatsumi Ishida, Kiyoshi Kuramoto, Yasuhiro Kawakatsu
EARTH PLANETS AND SPACE, 73, 1, SPRINGER, Dec. 2021, [Peer-reviewed]
English, Scientific journal, The science operations of the spacecraft and remote sensing instruments for the Martian Moon eXploration (MMX) mission are discussed by the mission operation working team. In this paper, we describe the Phobos observations during the first 1.5 years of the spacecraft's stay around Mars, and the Deimos observations before leaving the Martian system. In the Phobos observation, the spacecraft will be placed in low-altitude quasi-satellite orbits on the equatorial plane of Phobos and will make high-resolution topographic and spectroscopic observations of the Phobos surface from five different altitudes orbits. The spacecraft will also attempt to observe polar regions of Phobos from a three-dimensional quasi-satellite orbit moving out of the equatorial plane of Phobos. From these observations, we will constrain the origin of Phobos and Deimos and select places for landing site candidates for sample collection. For the Deimos observations, the spacecraft will be injected into two resonant orbits and will perform many flybys to observe the surface of Deimos over as large an area as possible.

還元型原始地球大気の流体力学的散逸
吉田 辰哉, 倉本 圭
遊星人, 30, 2, 52, 63, Jun. 2021, [Peer-reviewed], [Invited]

Hydrodynamic escape of an impact-generated reduced proto-atmosphere on Earth　　　　　　　　　　　　　　　
Tatsuya Yoshida, Kiyoshi Kuramoto
Monthly Notices of the Royal Astronomical Society, 505, 2, 2941, 2953, May 2021, [Peer-reviewed], [Last author]
English, Scientific journal

Implications of High Polarization Degree for the Surface State of Ryugu
Kuroda, D., Geem, J., Akitaya, H., Jin, S., Takahashi, J., Takahashi, K., Naito, H., Makino, K., Sekiguchi, T., Bach, Y.P., Seo, J., Sato, S., Sasago, H., Kawabata, K.S., Kawakami, A., Tozuka, M., Watanabe, M., Takagi, S., Kuramoto, K., Yoshikawa, M., Hasegawa, S., Ishiguro, M.
Astrophysical Journal Letters, 911, 2, IOP PUBLISHING LTD, Apr. 2021, [Peer-reviewed]
English, Scientific journal, The asteroid exploration project "Hayabusa2" has successfully returned samples from the asteroid (162173) Ryugu. In this study, we measured the linear polarization degrees of Ryugu using four ground-based telescopes from 2020 September 27 to December 25, covering a wide-phase angle (Sun-target-observer's angle) range from 28 degrees to 104 degrees. We found that the polarization degree of Ryugu reached 53% around a phase angle of 100 degrees, the highest value among all asteroids and comets thus far reported. The high polarization degree of Ryugu can be attributed to the scattering properties of its surface layers, in particular the relatively small contribution of multiply scattered light. Our polarimetric results indicate that Ryugu's surface is covered with large grains. On the basis of a comparison with polarimetric measurements of pulverized meteorites, we can infer the presence of submillimeter-sized grains on the surface layer of Ryugu. We also conjecture that this size boundary represents the grains that compose the aggregate. It is likely that a very brittle structure has been lost in the recovered samples, although they may hold a record of its evolution. Our data will be invaluable for future experiments aimed at reproducing the surface structure of Ryugu.

(85989) 1999 JD(6) : a first Barbarian asteroid detected by polarimetry in the NEA population
Daisuke Kuroda, Masateru Ishiguro, Hiroyuki Naito, Makoto Watanabe, Sunao Hasegawa, Seiko Takagi, Kiyoshi Kuramoto
ASTRONOMY & ASTROPHYSICS, 646, EDP SCIENCES S A, Feb. 2021, [Peer-reviewed]
English, Scientific journal, Context. To investigate the physical properties of the surface layers of small Solar System objects, we take advantage of the phase-angle dependence of the linear polarization degree, which varies with albedo, composition, and other factors. In particular, the angle at which the positive and negative are reversed is a polarimetric parameter known as inversion angle. A group with large inversion angles (the so-called Barbarians) is unusual and is also noteworthy because of their association with meteorites.Aims. We identified an object with such a large inversion angle in the near-Earth asteroids and derived previously unknown parameters, including the maximum polarization degree. By comparing the polarimetric parameters and spectral properties of meteorites, we inferred the surface conditions based on the degree of polarization of the asteroid.Methods. We carried out multiband polarization imaging observations of an L-type near-Earth asteroid, (85989) 1999 JD(6), at the Hokkaido University Observatory in 2015 and 2019, covering a wide range of phase angles 30 degrees -105 degrees. Of the polarimetric parameters, we derived the maximum value, inversion angle, and the slope at that angle from the phase angle-polarization degree curve.Results. We found that the inversion angle and the maximum polarization degree of 1999 JD(6) are 27 degrees and 13%. The inversion angle is significantly larger than those of the majority of all asteroids observed before, but is consistent with that of Barbarian asteroids. 1999 JD(6) is the first example belonging to this group that is also among the near-Earth asteroids.Conclusions. We claim that 1999 JD(6) is a member of the Barbarians and has rougher surface particles than lunar regolith.

Identification of the infrasound signals emitted by explosive eruption of Mt. Shinmoedake by three-dimensional ray tracing
Saito, H., Yamamoto, T., Nakajima, K., Kuramoto, K., Yamamoto, M.-Y.
Journal of the Acoustical Society of America, 149, 1, 591, 598, Acoustical Society of America (ASA), Jan. 2021, [Peer-reviewed]
Scientific journal

H2O2-induced greenhouse warming on oxidized early mars
Ito, Y., Hashimoto, G.L., Takahashi, Y.O., Ishiwatari, M., Kuramoto, K.
Astrophysical Journal, 893, 2, IOP PUBLISHING LTD, 28 Apr. 2020, [Peer-reviewed]
English, Scientific journal, The existence of liquid water within an oxidized environment on early Mars has been inferred by the Mn-rich rocks found during recent explorations on Mars. The oxidized atmosphere implied by the Mn-rich rocks would basically be comprised of CO2 and H2O without any reduced greenhouse gases such as H-2 and CH4. So far, however, it has been thought that early Mars could not have been warm enough to sustain water in liquid form without the presence of reduced greenhouse gases. Here, we propose that H2O2 could have been the gas responsible for warming the surface of the oxidized early Mars. Our one-dimensional atmospheric model shows that only 1 ppm of H2O2 is enough to warm the planetary surface because of its strong absorption at far-infrared wavelengths, in which the surface temperature could have reached over 273 K for a CO2 atmosphere with a pressure of 3 bar. A wet and oxidized atmosphere is expected to maintain sufficient quantities of H2O2 gas in its upper atmosphere due to its rapid photochemical production in slow condensation conditions. Our results demonstrate that a warm and wet environment could have been maintained on an oxidized early Mars, thereby suggesting that there may be connections between its ancient atmospheric redox state and possible aqueous environment.

System definition of Martian Moons Exploration (MMX)
Yasuhiro Kawakatsu, Kiyoshi Kuramoto, Tomohiro Usui, Hitoshi Ikeda, Kent Yoshikawa, Hirotaka Sawada, Naoya Ozaki, Takane Imada, Hisashi Otake, Kenichiro Maki, Masatsugu Otsuki, Robert Muller, Kris Zacny, Yasutaka Satoh, Stephane Mary, Markus Grebenstein, Ayumu Tokaji, Liang Yuying, Ferran Gonzalez Franquesa, Nishanth Pushparaj, Takuya Chikazawa
Proceedings of the International Astronautical Congress, IAC, 2020-October, 2020, [Peer-reviewed]
International conference proceedings, Martian Moons eXploration (MMX) is a mission to Martian moons under development in JAXA with international partners to be launched in 2024. This paper introduces the system definition and the latest status of MMX program. “How was water delivered to rocky planets and enabled the habitability of the solar system?” This is the key question to which MMX is going to answer in the context of our minor body exploration strategy preceded by Hayabusa and Hayabusa2. Solar system formation theories suggest that small bodies as comets and asteroids were delivery capsules of water, volatiles, organic compounds etc. from outside of the snow line to entitle the rocky planet region to be habitable. Mars was at the gateway position to witness the process, which naturally leads us to explore two Martian moons, Phobos and Deimos, to answer to the key question. The goal of MMX is to reveal the origin of the Martian moons, and then to make a progress in our understanding of planetary system formation and of primordial material transport around the border between the inner- and the outer-part of the early solar system. The mission is to survey two Martian moons, and return samples from one of them, Phobos. In view of the launch in 2024, the phase-A study was completed in February, 2020. The mission definition, mission scenario, system definition, critical technologies and programmatic framework are introduced int this paper.

The Importance of Phobos Sample Return for Understanding the Mars-Moon System
Usui, T., Bajo, K.-I., Fujiya, W., Furukawa, Y., Koike, M., Miura, Y.N., Sugahara, H., Tachibana, S., Takano, Y., Kuramoto, K.
Space Science Reviews, 216, 4, SPRINGER, Apr. 2020, [Peer-reviewed]
English, Scientific journal, Phobos and Deimos occupy unique positions both scientifically and programmatically on the road to the exploration of the solar system. Japan Aerospace Exploration Agency (JAXA) plans a Phobos sample return mission (MMX: Martian Moons eXploration). The MMX spacecraft is scheduled to be launched in 2024, orbit both Phobos and Deimos (multiple flybys), and retrieve and return >10 g of Phobos regolith back to Earth in 2029. The Phobos regolith represents a mixture of endogenous Phobos building blocks and exogenous materials that contain solar system projectiles (e.g., interplanetary dust particles and coarser materials) and ejecta from Mars and Deimos. Under the condition that the representativeness of the sampling site(s) is guaranteed by remote sensing observations in the geologic context of Phobos, laboratory analysis (e.g., mineralogy, bulk composition, O-Cr-Ti isotopic systematics, and radiometric dating) of the returned sample will provide crucial information about the moon's origin: capture of an asteroid or in-situ formation by a giant impact. If Phobos proves to be a captured object, isotopic compositions of volatile elements (e.g., D/H, C-13/C-12, N-15/N-14) in inorganic and organic materials will shed light on both organic-mineral-water/ice interactions in a primitive rocky body originally formed in the outer solar system and the delivery process of water and organics into the inner rocky planets.

Sluggish hydrodynamic escape of early Martian atmosphere with reduced chemical compositions
Yoshida, T., Kuramoto, K.
Icarus, 345, ACADEMIC PRESS INC ELSEVIER SCIENCE, Jul. 2020, [Peer-reviewed]
English, Scientific journal, Proto-Mars growing within the solar nebula may have maintained both the hydrogen-dominated solar component and the impact degassed component enriched in H-2, CH4 and CO as a proto-atmosphere. Such a protoatmosphere would experience hydrodynamic escape early in the history of Mars but its flux and duration of reduced composition remain highly uncertain. Here we develop a one-dimensional hydrodynamic escape model which includes radiative cooling processes and photochemical processes for a multi-component atmosphere and estimate the amount of atmosphere lost by hydrodynamic escape and the duration of early Martian atmosphere with reduced chemical compositions. The mass escape rate decreases more than one order of magnitude with increasing the mixing fraction of CH4 and CO >= 10% mainly because of the energy loss by radiative cooling by these infrared active chemical molecules. Concurrently, the mass fractionation between H-2 and other heavier species occurs more remarkably. Assuming that carbon species equivalent to 1 bar of CO2 was left behind when most H-2 completed its hydrodynamic escape, it possibly takes as long as 30 Myr for most H-2 to be lost by hydrodynamic escape. The total amount of CH4 and CO lost by hydrodynamic escape exceeds 10 bar, equivalent to 20 bar of CO2 when the initial atmosphere is hydrogen-rich, which may explain the paucity of CO2 on Mars compared to Earth and Venus. The isotopic fractionation during hydrodynamic escape is not enough to elevate the D/H ratio from the proto-solar value to the present value, but it can explain the C-13/C-12 ratio of present Mars. The reduced atmosphere with enriched in CH4 and CO may further continue until these species are almost fully oxidized through photolysis and hydrogen escape. Our result suggests that a reduced environment may have been kept and played an important role in producing warm and wet climate and serving organic matters on Mars.

Obliquity of an Earth-like Planet from Frequency Modulation of Its Direct-imaged Lightcurve: Mock Analysis from General Circulation Model Simulation
Nakagawa, Y., Kodama, T., Ishiwatari, M., Kawahara, H., Suto, Y., Takahashi, Y.O., Hashimoto, G.L., Kuramoto, K., Nakajima, K., Takehiro, S.-I., Hayashi, Y.-Y.
Astrophysical Journal, 898, 2, IOP PUBLISHING LTD, 28 Jul. 2020, [Peer-reviewed]
English, Scientific journal, Direct-imaging techniques of exoplanets have made significant progress recently and will eventually enable monitoring of photometric and spectroscopic signals of Earth-like habitable planets. The presence of clouds, however, would remain as one of the most uncertain components in deciphering such direct-imaged signals of planets. We attempt to examine how the planetary obliquity produces different cloud patterns by performing a series of general circulation model simulation runs using a set of parameters relevant for our Earth. Then we use the simulated photometric lightcurves to compute their frequency modulation that is due to the planetary spin-orbit coupling over an entire orbital period, and we attempt to see to what extent one can estimate the obliquity of an Earth twin. We find that it is possible to estimate the obliquity of an Earth twin within the uncertainty of several degrees with a dedicated 4 m space telescope at 10 pc away from the system if the stellar flux is completely blocked. While our conclusion is based on several idealized assumptions, a frequency modulation of a directly imaged Earth-like planet offers a unique methodology to determine its obliquity.

D/H Ratio in the Interiors of Rocky Protoplanets Accreting in the Solar Nebula
Saito, H., Kuramoto, K.
Astrophysical Journal, 889, 1, IOP PUBLISHING LTD, 23 Jan. 2020, [Peer-reviewed]
English, Scientific journal, The deuterium/hydrogen (D/H) ratio of primordial water partitioned into a planetary interior seems to be different on Earth and Mars. Water from volcanic rocks originating from Earth's deep mantle has a low D/H ratio with high He-3/He-4 ratios, implying that it was inherited partially from the solar nebula. In contrast, the D/H ratio of water in the Martian meteorites considered to represent the mantle does not trend toward that of the solar nebula. These differences may be owing to differences in the types of atmospheric structures formed on protoplanets accreting in the solar nebula. Using a 1D radiative-equilibrium model, we analyze the thermal structure of a hybrid-type protoatmosphere in which the solar nebula component dominates the upper layer while a degassed component dominates the lower layer. Our analysis implies Mars-sized protoplanets maintain a hybrid-type protoatmosphere and the D/H ratio of the lower atmosphere resembles that of the building blocks. Conversely, when the mass is larger than Mars-sized, the compositional stratification is collapsed by convective mixing of the solar nebula component with the degassed component, and the D/H ratio approaches that of the solar nebula. This tendency becomes stronger when the planetary mass is larger. If water vapor is distributed through a magma ocean into the planetary interior, Mars-sized protoplanets are likely to reflect the D/H ratios of the building blocks, while larger protoplanets are likely to have acquired a solar-nebula-like D/H ratio.

Diagnosing the clumpy protoplanetary disk of the UXor type young star GM Cephei
Huang, P.C., Chen, W.P., Mugrauer, M., Bischoff, R., Budaj, J., Burkhonov, O., Ehgamberdiev, S., Errmann, R., Garai, Z., Hsiao, H.Y., Hu, C.L., Janulis, R., Jensen, E.L.N., Kiyota, S., Kuramoto, K., Lin, C.S., Lin, H.C., Liu, J.Z., Lux, O., Naito, H., Neuhaüser, R., Ohlert, J., Pakštienė, E., Pribulla, T., Qvam, J.K.T., Raetz, S., Sato, S., Schwartz, M., Semkov, E., Takagi, S., Wagner, D., Watanabe, M., Zhang, Y.
Astrophysical Journal, 871, 2, 2019, [Peer-reviewed]
Scientific journal

A rover for the JAXA MMX mission to phobos
Stephan Ulamec, Patrick Michel, Matthias Grott, Ute Böttger, Heinz Wilhelm Hübers, Naomi Murdoch, Pierre Vernazza, Özgür Karatekin, Jörg Knollenberg, Konrad Willner, Markus Grebenstein, Stephane Mary, Pascale Chazalnoël, Jens Biele, Christian Krause, Tra Mi Ho, Caroline Lange, Jan Thimo Grundmann, Kaname Sasaki, Michael Maibaum, Oliver Küchemann, Josef Reill, Maxime Chalon, Stefan Barthelmes, Roy Lichtenheldt, Rainer Krenn, Michal Smisek, Jean Bertrand, Aurélie Moussi, Cedric Delmas, Simon Tardivel, Denis Arrat, Frans IJpelaan, Laurence Mélac, Laurence Lorda, Emile Remetean, Michael Lange, Olaf Mierheim, Siebo Reershemius, Tomohiro Usui, Moe Matsuoka, Tomoki Nakamura, Koji Wada, Hirdy Miyamoto, Kiyoshi Kuramoto, Julia LeMaitre, Guillaume Mas, Michel Delpech, Loisel Celine, Arthur Rafflegeau, Honorine Boirard, Roseline Schmisser, Cédric Virmontois, Celine Cenac-Morthe, Dominique Besson, Fernando Rull
Proceedings of the International Astronautical Congress, IAC, 2019-October, 2019, [Peer-reviewed]
International conference proceedings, Copyright © 2019 by the International Astronautical Federation (IAF). All rights reserved. The Martian Moons eXploration (MMX) is a mission by the Japan Aerospace Exploration Agency, JAXA, to the Martian moons Phobos and Deimos. It will primarily investigate the origin of this moon by bringing samples back from Phobos to Earth and deliver a small (about 25 kg) Rover to the surface. The Rover is a contribution by the Centre National d'Etudes Spatiales (CNES) and the German Aerospace Center (DLR). Its currently considered scientific payload consists of a thermal mapper (miniRAD), a Raman spectrometer (RAX) a stereo pair of cameras looking forward (NavCAM) and two cameras looking at the interface wheel-surface (WheelCAM) and consequent Phobos' regolith mechanical properties. The cameras will serve for both, technological and scientific needs. The MMX rover will be delivered from an altitude of <100 m and start uprighting and deploying wheels and a solar generator after having come to rest on the surface. It is planned to operate for three months on Phobos and provide unprecedented science while moving for a few meters to hundreds of meters. MMX will be launched in September 2024 and inserted into Mars orbit in 2025, the Rover delivery and operations are planned for 2026-2027.

Mission definition of Martian Moons exploration (MMX)
Yasuhiro Kawakatsu, Kiyoshi Kuramoto, Naoko Ogawa, Hitoshi Ikeda, Go Ono, Hirotaka Sawada, Takane Imada, Masatsugu Otsuki, Hisashi Otake, Robert Muller, Kris Zacny, Yasutaka Satoh, Kazuhiko Yamada, Stephane Mary, Markus Grebenstein, Kento Yoshikawa
Proceedings of the International Astronautical Congress, IAC, 2019-October, 2019, [Peer-reviewed]
International conference proceedings, Copyright © 2019 by the International Astronautical Federation (IAF). All rights reserved. Martian Moons eXploration (MMX) is a mission to Martian moons under study in JAXA with international partners to be launched in 2024. This paper introduces the mission definition and the latest status of MMX program. “How was water delivered to rocky planets and enabled the habitability of the solar system?” This is the key question to which MMX is going to answer in the context of our minor body exploration strategy preceded by Hayabusa and Hayabusa2. Solar system formation theories suggest that small bodies as comets and asteroids were delivery capsules of water, volatiles, organic compounds etc. from outside the snow line to entitle the rocky planet region to be habitable. Mars was at the gateway position to witness the process, which naturally leads us to explore two Martian moons, Phobos and Deimos, to answer to the key question. The goal of MMX is to reveal the origin of the Martian moons, and then to make a progress in our understanding of planetary system formation and of primordial material transport around the border between the inner- and the outer-part of the early solar system. The mission is to survey two Martian moons, and return samples from one of them. In view of the launch in 2024, the phase-A study is to be completed in this year. The mission definition, mission scenario, system description, and programmatic framework are introduced int this paper.

Science Objectives of the Ganymede Laser Altimeter (GALA) for the JUICE Mission
Jun KIMURA, Hauke HUSSMANN, Shunichi KAMATA, Koji MATSUMOTO, Jürgen OBERST, Gregor STEINBRÜGGE, Alexander STARK, Klaus GWINNER, Shoko OSHIGAMI, Noriyuki NAMIKI, Kay LINGENAUBER, Keigo ENYA, Kiyoshi KURAMOTO, Sho SASAKI
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN, 17, 2, 234, 243, Japan Society for Aeronautical and Space Sciences, 2019, [Peer-reviewed]
Scientific journal

Pluto’s ocean is capped and insulated by gas hydrates
Kamata, S., Nimmo, F., Sekine, Y., Kuramoto, K., Noguchi, N., Kimura, J., Tani, A.
Nature Geoscience, 12, 6, 407, 410, Springer Science and Business Media {LLC}, 20 Jun. 2019, [Peer-reviewed]
English, Scientific journal, Many icy Solar System bodies possess subsurface oceans. On Pluto, Sputnik Planitia's location near the equator suggests the presence of a subsurface ocean and a locally thinned ice shell. To maintain an ocean, Pluto needs to retain heat inside. On the other hand, to maintain large variations in its thickness, Pluto's ice shell needs to be cold. Here we show, by thermal evolution and viscous relaxation calculations, that the presence of a thin layer of clathrate hydrates (gas hydrates) at the base of the ice shell can explain both the long-term survival of the ocean and the maintenance of shell thickness contrasts. Clathrate hydrates act as a thermal insulator, preventing the ocean from completely freezing while keeping the ice shell cold and immobile. The most likely clathrate guest gas is methane, derived from precursor bodies and/or cracking of organic materials in the hot rocky core. Nitrogen molecules initially contained and/or produced later in the core would probably not be trapped as clathrate hydrates, instead supplying the nitrogen-rich surface and atmosphere. The formation of a thin clathrate hydrate layer cap to a subsurface ocean may be an important generic mechanism to maintain long-lived subsurface oceans in relatively large but minimally heated icy satellites and Kuiper belt objects.

Significantly high polarization degree of the very low-albedo asteroid (152679) 1998 KU2
Daisuke Kuroda, Masateru Ishiguro, Makoto Watanabe, Sunao Hasegawa, Tomohiko Sekiguchi, Hiroyuki Naito, Fumihiko Usui, Masataka Imai, Mitsuteru Sato, Kiyoshi Kuramoto
ASTRONOMY & ASTROPHYSICS, 611, EDP SCIENCES S A, Mar. 2018, [Peer-reviewed]
English, Scientific journal, We present a unique and significant polarimetric result regarding the near-Earth asteroid (152679) 1998 KU2, which has a very low geometric albedo. From our observations, we find that the linear polarization degrees of 1998 KU2 are 44.6 +/- 0.5% in the R-C band and 44.0 +/- 0.6% in the V band at a solar phase angle of 81.0 degrees. These values are the highest of any known airless body in the solar system (i.e., high-polarization comets, asteroids, and planetary satellites) at similar phase angles. This polarimetric observation is not only the first for primitive asteroids at large phase angles, but also for low-albedo (<0.1) airless bodies. Based on spectroscopic similarities and polarimetric measurements of materials that have been sorted by size in previous studies, we conjecture that 1998 KU2 has a highly microporous regolith structure comprising nano-sized carbon grains on the surface.

Mission design of Martian moons exploration (MMX)
Yasuhiro Kawakatsu, Kiyoshi Kuramoto, Tomohiro Usui, Hitoshi Ikeda, Naoya Ozaki, Nicola Baresi, Go Ono, Takane Imada, Takanobu Shimada, Hiroki Kusano, Hirotaka Sawada, Takashi Ozawa, Mitsuhisa Baba, Hisashi Otake
Proceedings of the International Astronautical Congress, IAC, 2018-October, 2018
International conference proceedings, Martian Moons eXploration (MMX) is a mission under study in ISAS/JAXA to be launched in 2024. This paper introduces the mission design of MMX mission. “How was water delivered to rocky planets and enabled the habitability of the solar system?” This is the key question to which MMX is going to answer. Solar system formation theories suggest that rocky planets must have been born dry. Delivery of water, volatiles, organic compounds etc. from outside the snow line entitles the rocky planet region to be habitable. Small bodies as comets and asteroids play the role of delivery capsules. Then, dynamics of small bodies around the snow line in the early solar system is the issue that needs to be understood. Mars was at the gateway position to witness the process, which naturally leads us to explore two Martian moons, Phobos and Deimos, to answer to the key question. The goal of MMX is to reveal the origin of the Martian moons, and then to make a progress in our understanding of planetary system formation and of primordial material transport around the border between the inner- and the outer-part of the early solar system. The mission is to survey two Martian moons, and return samples from one of them. Following the mission concepts study results presented in the previous conference, the following items will be reported in this paper. First, based on the mission goals and objectives defined, the requirements to the systems and operations are derived and their feasibility is evaluated. Second, as to the key technologies issues identified, partial models are built and their performance is evaluated. And third, collaborations with overseas space agency are discussed and the programmatic framework is defined.

Breaking the Habit: The Peculiar 2016 Eruption of the Unique Recurrent Nova M31N 2008-12a
Henze, M., Henze, M., Darnley, M.J., Williams, S.C., Kato, M., Hachisu, I., Anupama, G.C., Arai, A., Boyd, D., Burke, D., Ciardullo, R., Chinetti, K., Cook, L.M., Cook, M.J., Erdman, P., Gao, X., Harris, B., Hartmann, D.H., Hornoch, K., Horst, J.C., Hounsell, R., Husar, D., Itagaki, K., Kabashima, F., Kafka, S., Kaur, A., Kiyota, S., Kojiguchi, N., Kučáková, H., Kuramoto, K., Maehara, H., Mantero, A., Masci, F.J., Matsumoto, K., Naito, H., Ness, J.-U., Nishiyama, K., Oksanen, A., Osborne, J.P., Page, K.L., Paunzen, E., Pavana, M., Pickard, R., Prieto-Arranz, J., Rodríguez-Gil, P., Sala, G., Sano, Y., Shafter, A.W., Sugiura, Y., Tan, H., Tordai, T., Vraštil, J., Wagner, R.M., Watanabe, F., Williams, B.F., Bode, M.F., Bruno, A., Buchheim, B., Crawford, T., Goff, B., Hernanz, M., Igarashi, A.S., José, J., Motta, M., O'Brien, T.J., Oswalt, T., Poyner, G., Ribeiro, V.A.R.M., Sabo, R., Shara, M.M., Shears, J., Starkey, D., Starrfield, S., Woodward, C.E.
Astrophysical Journal, 857, 1, 2018, [Peer-reviewed]
Scientific journal

Mass-independent oxygen isotope variation in the solar nebula
Young, E.D., Kuramoto, K., Marcus, R.A., Yurimoto, H., Jacobsen, S.B.
Oxygen in the Solar System, 68, 1, 187, 218, Mineralogical Society of America, 2018, [Peer-reviewed]
English, Scientific journal, In this chapter we compare and contrast chemical and photochemical pathways for mass-independent fractionation (MIF) of oxygen isotopes in the solar nebula. We begin by assessing the galactic evolution model for oxygen isotope variation in the Solar System in order to compare the predictions of a leading nucleosynthetic model with those of the chemical models. There are two fundamentally different classes of possible chemical mechanisms for mass-independent oxygen isotope fractionation in the early Solar System. One is symmetry-induced intramolecular vibrational disequilibrium of vibrationally excited reactant oxygen-bearing molecules. The other is isotope selective photodissociation of CO coupled with self-shielding and formation of H(2)O- Symmetry-induced fractionation is an experimentally verified process with solid theoretical foundations. It is observed to occur in Earth's atmosphere. It could have resulted in preservation of oxygen MIF effects only if mediated by dust grain surfaces. CO self-shielding is an attractive hypothesis for the origin of mass-independent oxygen isotope fractionation in the early Solar System because it appeals to a process that apparently occurs in the interstellar medium, but it lacks experimental verification. Three astrophysical settings for CO self-shielding are proposed as sites for generating Delta(17)O variability in the early Solar System. One is the inner annulus of the protostellar disk at relatively high temperature. Another is the surface of the disk high above the midplane where light from the central star grazes theas and dust of the disk, resulting in a zone of active CO predissociation and self-shielding. Interstellar light illuminating the disk at high incident angles causes a similar horizon of CO photodestruction. Variations in (16)O could also have been inherited from self-shielding by CO in the molecular cloud that gave rise to the protosun. The overall consequence of CO self-shielding is conversion of CO gas to (16)O-poor H(2)O. A key difference between galactic evolution, chemically-induced MIF effects, and CO self-shielding is the predicted relative oxygen isotopic compositions of primeval dust and the Sun. Therefore, the oxygen isotopic composition of the Sun will be a crucial arbiter that may permit us to narrow the list of possible origins for oxygen MIF in the early Solar System.

Extremely strong polarization of an active asteroid (3200) Phaethon
Ito, T., Ishiguro, M., Arai, T., Imai, M., Sekiguchi, T., Bach, Y.P., Kwon, Y.G., Kobayashi, M., Ishimaru, R., Naito, H., Watanabe, M., Kuramoto, K.
Nature Communications, 9, 1, 2486, NATURE PUBLISHING GROUP, Jun. 2018, [Peer-reviewed]
English, Scientific journal, The near-Earth asteroid (3200) Phaethon is the parent body of the Geminid meteor stream. Phaethon is also an active asteroid with a very blue spectrum. We conducted polarimetric observations of this asteroid over a wide range of solar phase angles a during its close approach to the Earth in autumn 2016. Our observation revealed that Phaethon exhibits extremely large linear polarization: P = 50.0 +/- 1.1% at a = 106.5 degrees, and its maximum is even larger. The strong polarization implies that Phaethon's geometric albedo is lower than the current estimate obtained through radiometric observation. This possibility stems from the potential uncertainty in Phaethon's absolute magnitude. An alternative possibility is that relatively large grains (similar to 300 mu m in diameter, presumably due to extensive heating near its perihelion) dominate this asteroid's surface. In addition, the asteroid's surface porosity, if it is substantially large, can also be an effective cause of this polarization.

D/H ratio of inner proto planets
Saito H., Kuramoto K.
Planetary People - The Japanese Society for Planetary Sciences, 27, 3, 229, 234, The Japanese Society for Planetary Sciences, 2018, [Peer-reviewed]
Japanese, <p>形成期の惑星内部に取り込まれた初生水の D/H 比は地球と火星で異なるらしい．始原マントルにソースを持つと考えられる噴出岩中のメルト包有物中の H2O は，地球試料においては，星雲ガスを取り込んだことを示唆する低い D/H 比を示す一方で，火星試料においては，炭素質コンドライトに近い D/H 比を示す．両者の D/H 比の差異は，星雲内で集積する原始惑星上における原始大気の構造が惑星質量に依存しているためであるかもしれない．新たな一次元大気構造数値モデリングの結果によれば， 火星質量程度の原始惑星の場合，上層に星雲ガス成分，下層に衝突脱ガス成分からなる成層した混成型原始大気が形成し，接している原始マントルは材料物質に含まれる H2O の D/H 比を獲得することができる．これに対して，火星質量以上の原始惑星の場合，対流により起源の異なる両成分が混合し，下層大気の D/H 比は星雲ガスの値に接近する．これによって大質量の惑星の始原マントルは，星雲ガスに近い値の D/H 比を獲得できた可能性がある．</p>

Martian Moons eXploration MMX elucidating the formation of habitable planets in the solar system
Kuramoto K., Morota T., Nagaoka H., Nakagawa H., Nakamura T., Ogawa K., Otake H., Ozaki M., Sasaki S., Senshu H., Tachibana S., Kawakatsu Y., Terada N., Usui T., Wada K., Watanabe S., MMX study team, Fujimoto M., Genda H., Hirata N., Imamura T., Kameda S., Matsumoto K., Miyamoto H.
Planetary People - The Japanese Society for Planetary Sciences, 27, 3, 207, 215, The Japanese Society for Planetary Sciences, 2018, [Peer-reviewed]
Japanese, <p>火星衛星Phobosからのサンプルリターンに挑む火星衛星探査計画 (Martian Moons eXploration: MMX) は，現在，宇宙航空研究開発機構 (JAXA) プリプロジェクトとして，2024年の打ち上げと5年の往還期間を設定し，精力的な検討・初期開発が進められている．MMXは，サンプル分析，Deimosを加えた火星衛星の近接観測，そして火星大気および火星圏のモニタリング観測を組み合わせることにより，惑星に寄りそう衛星という切り口と視座から，太陽系における大気と水を湛えたハビタブル惑星の形成と進化の解明に迫ろうとしている．</p>

Significantly high polarization degree of the very low-albedo asteroid (152679) 1998 KU2
Daisuke Kuroda, Masateru Ishiguro, Makoto Watanabe, Sunao Hasegawa, Tomohiko Sekiguchi, Hiroyuki Naito, Fumihiko Usui, Masataka Imai, Mitsuteru Sato, Kiyoshi Kuramoto
Astronomy & Astrophysics, 611, {EDP} Sciences, Nov. 2017, [Peer-reviewed]
English, Scientific journal, We present a unique and significant polarimetric result regarding the near-Earth asteroid (152679) 1998 KU2, which has a very low geometric albedo. From our observations, we find that the linear polarization degrees of 1998 KU2 are 44.6 ± 0.5% in the RC band and 44.0 ± 0.6% in the V band at a solar phase angle of 81.0°. These values are the highest of any known airless body in the solar system (i.e., high-polarization comets, asteroids, and planetary satellites) at similar phase angles. This polarimetric observation is not only the first for primitive asteroids at large phase angles, but also for low-albedo (<
0.1) airless bodies. Based on spectroscopic similarities and polarimetric measurements of materials that have been sorted by size in previous studies, we conjecture that 1998 KU2 has a highly microporous regolith structure comprising nano-sized carbon grains on the surface.

Polarimetric Study of Near-Earth Asteroid (1566) Icarus
Masateru Ishiguro, Daisuke Kuroda, Makoto Watanabe, Yoonsoo P. Bach, Jooyeon Kim, Mingyeong Lee, Tomohiko Sekiguchi, Hiroyuki Naito, Katsuhito Ohtsuka, Hidekazu Hanayama, Sunao Hasegawa, Fumihiko Usui, Seitaro Urakawa, Masataka Imai, Mitsuteru Sato, Kiyoshi Kuramoto
The Astronomical Journal, 154, 5, 180, 180, American Astronomical Society, Oct. 2017, [Peer-reviewed]
Scientific journal

Formation of a hybrid-type proto-atmosphere on Mars accreting in the solar nebula
Hiroaki Saito, Kiyoshi Kuramoto
Monthly Notices of the Royal Astronomical Society, 475, 1, 1274, 1287, Oxford University Press ({OUP}), 2017, [Peer-reviewed]
English, Scientific journal, Recent studies of the chronology of Martian meteorites suggest that the growth of Mars was almost complete within a few Myr after the birth of the Solar system. During such rapid accretion, proto-Mars likely gravitationally maintained both the solar nebula component and the impact degassing component, containing H2O vapour and reduced gas species, as a proto-atmosphere to be called a hybrid-type proto-atmosphere. Here we numerically analyse the mass and composition of the degassed component and the atmospheric thermal structure sustained by accretional heating. Our results predict that a growing Mars possibly acquired a massive and hot hybrid-type proto-atmosphere with surface pressure and temperature greater than several kbar and 2000 K, respectively, which is sufficient to produce a deep magma ocean. In such a high-temperature and high-pressure environment, a significant amount of H2O, CH4, CO, and H-2 is expected to be partitioned into the planetary interior, although this would strongly depend on the dynamics of the magma ocean and mantle solidification. The dissolved H2O may explain the wet Martian mantle implied from basaltic Martian meteorites. Along with the remnant reduced atmosphere after the hydrodynamic atmospheric escape, dissolved reduced gas species may have maintained an earliest Martian surface environment that allowed prebiotic chemical evolution and liquid H2O activities.

The circulation pattern and day-night heat transport in the atmosphere of a synchronously rotating aquaplanet: Dependence on planetary rotation rate
Noda, S., Ishiwatari, M., Nakajima, K., Takahashi, Y.O., Takehiro, S., Onishi, M., Hashimoto, G.L., Kuramoto, K., Hayashi, Y.-Y.
Icarus, 282, 1, 18, ACADEMIC PRESS INC ELSEVIER SCIENCE, 2017, [Peer-reviewed]
English, Scientific journal, In order to investigate a possible variety of atmospheric states realized on a synchronously rotating aqua planet, an experiment studying the impact of planetary rotation rate is performed using an atmospheric general circulation model (GCM) with simplified hydrological and radiative processes. The entire planetary surface is covered with a swamp ocean. The value of planetary rotation rate is varied from zero to the Earth's, while other parameters such as planetary radius, mean molecular weight and total mass of atmospheric dry components, and solar constant are set to the present Earth's values. The integration results show that the atmosphere reaches statistically equilibrium states for all runs; none of the calculated cases exemplifies the runaway greenhouse state. The circulation patterns obtained are classified into four types: Type-I characterized by the dominance of a day-night thermally direct circulation, Type-II characterized by a zonal wave number one resonant Rossby wave over a meridionally broad westerly jet on the equator, Type-III characterized by a long time scale north-south asymmetric variation, and Type-IV characterized by a pair of mid-latitude westerly jets. With the increase of planetary rotation rate, the circulation evolves from Type-I to Type-II and then to Type-III gradually and smoothly, whereas the change from Type-Ill to Type-IV is abrupt and discontinuous. Over a finite range of planetary rotation rate, both Types-III and -IV emerge as statistically steady states, constituting multiple equilibria. In spite of the substantial changes in circulation, the net energy transport from the day side to the night side remains almost insensitive to planetary rotation rate, although the partition into dry static energy and latent heat energy transports changes. The reason for this notable insensitivity is that the outgoing longwave radiation over the broad area of the day side is constrained by the radiation limit of a moist atmosphere, so that the transport to the night side, which is determined as the difference between the incoming solar radiation and the radiation limit, cannot change greatly. (C) 2016 The Authors. Published by Elsevier Inc.

Mission concept of martian moons eXploration (MMX)
Yasuhiro Kawakatsu, Kiyoshi Kuramoto, Naoko Ogawa, Hitoshi Ikeda, Yuya Mimasu, Go Ono, Hirotaka Sawada, Kento Yoshikawa, Takane Imada, Hisashi Otake, Hiroki Kusano, Kazuhiko Yamada, Masatsugu Otsuki, Mitsuhisa Baba
Proceedings of the International Astronautical Congress, IAC, 5, 2732, 2740, 2017, [Peer-reviewed]
English, International conference proceedings, © Copyright 2017 by the International Astronautical Federation (IAF). All rights reserved. Martian Moons eXploration (MMX) is a mission under study in ISAS/JAXA to be launched in 2020s. This paper introduces the concept of MMX mission. "How was water delivered to rocky planets and enabled the habitability of the solar system?" This is the key question to which MMX is going to answer. Solar system formation theories suggest that rocky planets must have been born dry. Delivery of water, volatiles, organic compounds etc. from outside the snow line entitles the rocky planet region to be habitable. Small bodies as comets and asteroids play the role of delivery capsules. Then, dynamics of small bodies around the snow line in the early solar system is the issue that needs to be understood. Mars was at the gateway position to witness the process, which naturally leads us to explore two Martian moons, Phobos and Deimos, to answer to the key question. The goal of MMX is to reveal the origin of the Martian moons, and then to make a progress in our understanding of planetary system formation and of primordial material transport around the border between the inner- and the outer-part of the early solar system. On the origin of Martian moons, there are two leading hypotheses, "Captured primordial asteroid" and "Giant Impact". We decide to collect samples from a Martian moon to conclude this discussion, and on the conclusion, to investigate further to improve our understanding of material distributions and transports at the edge of the inner part of the early solar system as well as of planetary formations. Moreover, circum-Martian environment will be measured and Martian atmosphere will be observed to improve our views of evolutions of Martian moons as well as Mars surface environmental transition. In the conceptual design phase, the goals and objectives of the mission are defined, and the feasibility of the mission is evaluated. Fundamental engineering options are listed up, and trade-off studies are conducted to define baseline plan. Key technology issues are identified and their technology readiness is evaluated. The results will be shown in the paper.

Tidal deformation of Ganymede: Sensitivity of Love numbers on the interior structure
Shunichi Kamata, Jun Kimura, Koji Matsumoto, Francis Nimmo, Kiyoshi Kuramoto, Noriyuki Namiki
Journal of Geophysical Research: Planets, 121, 7, 1362, 1375, Wiley-Blackwell, Jul. 2016, [Peer-reviewed]
Scientific journal

Tidal deformation of Ganymede: Sensitivity of Love numbers on the interior structure
Kamata, S., Kimura, J., Matsumoto, K., Nimmo, F., Kuramoto, K., Namiki, N.
Journal of Geophysical Research: Planets, 121, 7, 1362, 1375, AMER GEOPHYSICAL UNION, 2016, [Peer-reviewed]
English, Scientific journal, Tidal deformation of icy satellites provides crucial information on their subsurface structures. In this study, we investigate the parameter dependence of the tidal displacement and potential Love numbers (i.e., h(2) and k(2), respectively) of Ganymede. Our results indicate that Love numbers for Ganymede models without a subsurface ocean are not necessarily smaller than those with a subsurface ocean. The phase lag, however, depends primarily on the presence/absence of a subsurface ocean. Thus, the determination of the phase lag would be of importance to infer whether Ganymede possesses a subsurface ocean or not based only on geodetic measurements. Our results also indicate that the major control on Love numbers is the thickness of the ice shell if Ganymede possesses a subsurface ocean. This result, however, does not necessarily indicate that measurement of either of h(2) or k(2) alone is sufficient to estimate the shell thickness; while a thin shell leads to large h(2) and k(2) independent of parameters, a thick shell does not necessarily lead to small h(2) and k(2). We found that to reduce the uncertainty in the shell thickness, constraining k(2) in addition to h(2) is necessary, highlighting the importance of collaborative analyses of topography and gravity field data.

A review by the chief editors of some of the most popular papers published by PEPS in 2014–2015
Yasufumi Iryu, Kiyoshi Kuramoto, Masaki Satoh, Jun Matsumoto, Shoichi Yoshioka, Hodaka Kawahata, Ryuji Tada
Progress in Earth and Planetary Science, 3, 1, Springer Nature, Jan. 2016, [Peer-reviewed]
English, Scientific journal

The relative timing of Lunar Magma Ocean solidification and the Late Heavy Bombardment inferred from highly degraded impact basin structures
Kamata, S., Sugita, S., Abe, Y., Ishihara, Y., Harada, Y., Morota, T., Namiki, N., Iwata, T., Hanada, H., Araki, H., Matsumoto, K., Tajika, E., Kuramoto, K., Nimmo, F.
Icarus, 250, 492, 503, ACADEMIC PRESS INC ELSEVIER SCIENCE, 2015, [Peer-reviewed]
English, Scientific journal, The solidification of the Lunar Magma Ocean (LMO) and formation of impact basins are important events that took place on the early Moon. The relative timing of these events, however, is poorly constrained. The aim of this study is to constrain the formation ages of old impact basins based on inferences of their thermal state. Most proposed basins formed before Pre-Nectarian (PN) 5 stage do not exhibit clear concentric features in either topography or gravity, suggesting substantial viscous lateral flow in the crust. Recent geodetic measurements reveal that the lunar crust is thinner than previously estimated, indicating that an extremely high crustal temperature is required for lateral flow to occur. In this study, we calculate lunar thermal evolution and viscoelastic deformation of basins and investigate the thermal state at the time of basin formation using recent crustal thickness models. We find that a Moho temperature >1300-1400 K at the time of basin formation is required for substantial viscous relaxation of topography to occur; the implied elastic thickness at the time of loading is <30 km. Such a high temperature can be maintained only for a short time (i.e., <50 Myr for most conditions) after solidification of the LMO or after mantle overturn if it took place; relaxed impact basins forming >= 150 Myr later than LMO solidification are unlikely. This result is in conflict with an intensive Late Heavy Bombardment (LHB) model, which assumes that most impact basins were formed at similar to 3.9 Ga, since it requires LMO solidification time much later than previous theoretical estimates. Either the LHB was moderate, or the majority of proposed early PN basins were not in fact formed by impacts. (C) 2014 Elsevier Inc. All rights reserved.

Numerical simulations of Jupiter's moist convection layer: Structure and dynamics in statistically steady states
Sugiyama, K., Nakajima, K., Odaka, M., Kuramoto, K., Hayashi, Y.-Y.
Icarus, 229, 71, 91, ACADEMIC PRESS INC ELSEVIER SCIENCE, 2014, [Peer-reviewed]
English, Scientific journal, A series of long-term numerical simulations of moist convection in Jupiter's atmosphere is performed in order to investigate the idealized characteristics of the vertical structure of multi-composition clouds and the convective motions associated with them, varying the deep abundances of condensable gases and the autoconversion time scale, the latter being one of the most questionable parameters in cloud microphysical parameterization. The simulations are conducted using a two-dimensional cloud resolving model that explicitly represents the convective motion and microphysics of the three cloud components, H2O, NH3, and NH4SH imposing a body cooling that substitutes the net radiative cooling. The results are qualitatively similar to those reported in Sugiyama et al. (Sugiyama, K. et al. [2011]. Intermittent cumulonimbus activity breaking the three-layer cloud structure of Jupiter. Geophys. Res. Lett. 38, L13201. doi:10.1029/2011GL047878): stable layers associated with condensation and chemical reaction act as effective dynamical and compositional boundaries, intense cumulonimbus clouds develop with distinct temporal intermittency, and the active transport associated with these clouds results in the establishment of mean vertical profiles of condensates and condensable gases that are distinctly different from the hitherto accepted three-layered structure (e.g., Atreya, S.K., Romani, P.N. [1985]. Photochemistry and clouds of Jupiter, Saturn and Uranus. In: Recent Advances in Planetary Meteorology. Cambridge Univ. Press, London, pp. 17-68). Our results also demonstrate that the period of intermittent cloud activity is roughly proportional to the deep abundance of H2O gas. The autoconversion time scale does not strongly affect the results, except for the vertical profiles of the condensates. Changing the autoconversion time scale by a factor of 100 changes the intermittency period by a factor of less than two, although it causes a dramatic increase in the amount of condensates in the upper troposphere.
The moist convection layer becomes potentially unstable with respect to an air parcel rising from below the H2O lifting condensation level (LCL) well before the development of cumulonimbus clouds. The instability accumulates until an appropriate trigger is provided by the H2O condensate that falls down through the H2O LCL; the H2O condensate drives a downward flow below the H2O LCL as a result of the latent cooling associated with the re-evaporation of the condensate, and the returning updrafts carry moist air from below to the moist convection layer. Active cloud development is terminated when the instability is completely exhausted. The period of intermittency is roughly equal to the time obtained by dividing the mean temperature increase, which is caused by active cumulonimbus development, by the body cooling rate. 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Corrigendum to "Numerical simulations of Jupiter's moist convection layer: Structure and dynamics in statistically steady states" [Icarus 229 (2014) 71-91]
Sugiyama, K., Nakajima, K., Odaka, M., Kuramoto, K., Hayashi, Y.-Y.
Icarus, 231, 407, 408, ACADEMIC PRESS INC ELSEVIER SCIENCE, 2014, [Peer-reviewed]
English, Scientific journal

Near-infrared brightness of the Galilean satellites eclipsed in Jovian shadow: A New Technique to Investigate Jovian Upper Atmosphere
Tsumura, K., Arimatsu, K., Egami, E., Hayano, Y., Honda, C., Kimura, J., Kuramoto, K., Matsuura, S., Minowa, Y., Nakajima, K., Nakamoto, T., Shirahata, M., Surace, J., Takahashi, Y., Wada, T.
Astrophysical Journal, 789, 2, 2014, [Peer-reviewed]
Scientific journal, Based on observations from the Hubble Space Telescope and the Subaru Telescope, we have discovered that Europa, Ganymede, and Callisto are bright around 1.5 μm even when not directly lit by sunlight. The observations were conducted with non-sidereal tracking on Jupiter outside of the field of view to reduce the stray light subtraction uncertainty due to the close proximity of Jupiter. Their eclipsed luminosity was 10 -6 -10 -7 of their uneclipsed brightness, which is low enough that this phenomenon has been undiscovered until now. In addition, Europa in eclipse was < 1/10 of the others at 1.5 μm, a potential clue to the origin of the source of luminosity. Likewise, Ganymede observations were attempted at 3.6 μm by the Spitzer Space Telesc ope, but it was not detected, suggesting a significant wavelength dependence. It is still unknown why they are luminous even when in the Jovian shadow, but forward-scattered sunlight by hazes in the Jovian upper atmosphere is proposed as the most plausible candidate. If this is the case, observations of these Galilean satellites while eclipsed by the Jovian shadow provide us with a new technique to investigate the Jovian atmospheric composition. Investigating the transmission spectrum of Jupiter by this method is important for investigating the atmosphere of extrasolar giant planets by transit spectroscopy. © 2014. The American Astronomical Society. All rights reserved.

Effective hydrodynamic hydrogen escape from an early Earth atmosphere inferred from high-accuracy numerical simulation
Kiyoshi Kuramoto, Takafumi Umemoto, Masaki Ishiwatari
Earth and Planetary Science Letters, 375, 312, 318, Elsevier {BV}, Aug. 2013, [Peer-reviewed]
English, Scientific journal, Hydrodynamic escape of hydrogen driven by solar extreme ultraviolet (EUV) radiation heating is numerically simulated by using the constrained interpolation profile scheme, a high-accuracy scheme for solving the one-dimensional advection equation. For a wide range of hydrogen number densities at the lower boundary and solar EUV fluxes, more than half of EUV heating energy is converted to mechanical energy of the escaping hydrogen. Less energy is lost by downward thermal conduction even giving low temperature for the atmospheric base. This result differs from a previous numerical simulation study that yielded much lower escape rates by employing another scheme in which relatively strong numerical diffusion is implemented. Because the solar EUV heating effectively induces hydrogen escape, the hydrogen mixing ratio was likely to have remained lower than 1 vol% in the anoxic Earth atmosphere during the Archean era. (C) 2013 Elsevier B.V. All rights reserved.

Atmospheric structure and cloud convection in Jupiter's atmosphere　　　　　　　　　　　　　　　
K. Sugiyama, K. Nakajima, M. Odaka, M. Ishiwatari, K. Kuramoto, Y. O. Takahashi, Y.-Y. Hayashi
Planetary People, 21, 1, 39, 44, Mar. 2012, [Peer-reviewed]
Japanese

Exploration of Enceladus' water-rich plumes toward understanding chemistry and biology of the interior ocean (Special issue: Planetary exploration in a coming decade activity: Reports of 2nd stage)
Sekine Y., Yabuta H., Kimura J., Furukawa Y., Takano Y., Yano H., Funase R., Takai K., Ishihara M., Shibuya T., Tachibana S., Kuramoto K.
Planetary People - The Japanese Society for Planetary Sciences, 21, 3, 229, 238, The Japanese Society for Planetary Sciences, 2012
Japanese, エンセラダスの南極付近から噴出するプリュームの発見は,氷衛星の内部海の海水や海中の揮発性成分や固体成分の直接サンプリングの可能性を示した大きなブレイクスルーであるといえる.これまでカッシーニ探査によって,プリューム物質は岩石成分と相互作用する液体の内部海に由来していることが明らかになったが,サンプリング時の相対速度が大きいこと,質量分析装置の分解能が低いことなどの問題があり,内部海の化学組成や温度条件,海の存続時間など,生命存在の可能性を制約できる情報は乏しい.本論文では,エンセラダス・プリューム物質の高精度その場質量分析とサンプルリターンによる詳細な物質分析を行うことで,内部海の化学組成の解明,初期太陽系物質進化の制約,そして生命存在可能性を探ることを目的とする探査計画を提案する.本提案は,"宇宙に生命は存在するのか"という根源的な問いに対して,理・工学の様々な分野での次世代を担う若手研究者が惑星探査に参入し結集する点が画期的であり,我が国の科学・技術界全体に対しても極めて大きな波及効果をもつ.

A repository for knowledge of planetary science served by Center for Planetary Science (CPS)
Sugiyama K., Tani I., Katoh N., Umemoto T., Oshikawa T., Mikami T., Kuramoto K., Hayashi Y., Nakagawa Y., Center for Planetary Science, Suzuki A., Takahashi J., Nakamura T., Manabe S., Sakai S., Tsurumaki R., Nakaoka R., Tatsumi S.
Planetary People - The Japanese Society for Planetary Sciences, 21, 4, 368, 376, The Japanese Society for Planetary Sciences, 2012
Japanese, 惑星科学研究センター(CPS)では,国内外の惑星科学研究者の教育研究活動を広く支援する「場」の1つとして,先端的な知見の共有を容易にするための知見アーカイブを構築している.この取り組みは, 2000年に発足した北海道大学理学部の有志活動であるmosirプロジェクトを継承・発展させたものであり,現在に至るまでの活動で蓄積した研究会やセミナーでの研究発表を始めとするコンテンツは1,100本以上にのぼる.本稿ではCPSの知見アーカイブの概要を示すと共に,知見アーカイブの利便性を向上させるための取り組みや作業コストの低減を図るための取り組みを解説する.

Weak-field dynamo emerging in a rotating spherical shell with stress-free top and no-slip bottom boundaries
Youhei Sasaki, Shin-ichi Takehiro, Kiyoshi Kuramoto, Yoshi-Yuki Hayashi
Physics of the Earth and Planetary Interiors, 188, 3-4, 203, 213, Elsevier {BV}, Oct. 2011, [Peer-reviewed]
English, Scientific journal, Numerical experiments are performed in order to investigate an MHD dynamo in a rotating spherical shell with stress-free top and no-slip bottom boundaries. The Ekman number, the Prandtl number, and the ratio of inner to outer radii are fixed as 10(-3), 1, and 0.35, respectively. The magnetic Prandtl number is varied from 5 to 50, and the modified Rayleigh number is increased from 1.5 to 10 times the critical Rayleigh number. The initial imposed magnetic field is either a weak or strong magnetic field, where the magnetic energy of the initial field is approximately two orders of magnitude smaller or larger than the kinetic energy of the quasi-steady state of non-magnetic thermal convection.For cases involving a weak initial magnetic field, self-sustained dynamo solutions are established when the magnetic Prandtl number is larger than or equal to 5, and the modified Rayleigh number is larger than or equal to 5 times the critical Rayleigh number. The solutions are categorized as a weak field-dynamo, where the mean magnetic energy is one order of magnitude smaller than the mean kinetic energy. The dynamo solutions are characterized by a radially two-layer spatial structure. The upper layer is dominated by a strong prograde zonal mean zonal flow with large-scale prograde propagating spiral vortices having a longitudinal wavenumber of 3. Toroidal kinetic energy is converted to toroidal magnetic energy through stretching of the field lines by large-scale prograde propagating spiral vortices. On the other hand, the lower layer contains small-scale retrograde propagating columnar convective vortices having a longitudinal wavenumber of 8. The magnetic field lines are not concentrated in the vortices, but rather wind around the vortices in each layer. Poloidal kinetic energy is converted to poloidal magnetic energy through winding of the field lines around small-scale retrograde propagating columnar convective vortices.For cases involving a strong initial magnetic field, self-sustained dynamo solutions are established when the magnetic Prandtl number is greater than or equal to 4 and the modified Rayleigh number is greater than or equal to 3 times the critical Rayleigh number. In contrast with the cases involving a weak initial magnetic field, all of the dynamo solutions are strong-field solutions.Bistability is observed when the magnetic Prandtl number is 5, and the modified Rayleigh number is approximately equal to 10 times the critical Rayleigh number, where weak-field and strong-field dynamo solutions coexist. However, transition between the weak-field and strong-field solutions does not occur in this case. (C) 2011 Elsevier B.V. All rights reserved.

Sublimation’s impact on temporal change of albedo dichotomy on Iapetus
Jun Kimura, Taichi Kawamura, Hisataka Morito, Tomokatsu Morota, Chikatoshi Honda, Kiyoshi Kuramoto, Tatsuaki Okada
Icarus, 214, 2, 596, 605, Elsevier {BV}, Aug. 2011, [Peer-reviewed]
English, Scientific journal, Iapetus, one of the saturnian moons, has an extreme albedo contrast between the leading and trailing hemispheres. The origin of this albedo dichotomy has led to several hypotheses, however it remains controversial. To clarify the origin of the dichotomy, the key approach is to investigate the detailed distribution of the dark material. Recent studies of impact craters and surface temperature from Cassini spacecraft data implied that sublimation of H(2)O ice can occur on Iapetus' surface. This ice sublimation can change the albedo distribution on the moon with time.In this study, we evaluate the effect of ice sublimation and simulate the temporal change of surface albedo. We assume the dark material and the bright ice on the surface to be uniformly mixed with a certain volume fraction, and the initial albedo distribution to incorporate the dark material deposits on the surface. That is, the albedo at the apex is lowest and concentrically increases in a sinusoidal pattern. This situation simulates that dark materials existed around the Iapetus' orbit billions of years ago, and the synchronously rotating Iapetus swept the material and then deposited it on its surface. The evolution of the surface albedo during 4.0 Gyr is simulated by estimating the surface temperature from the insolation energy on Iapetus including the effect of Saturn's eccentricity and Iapetus' obliquity precession, and evaluating the sublimation rate of H(2)O ice from the Iapetus' surface.As a result, we found that the distribution of the surface albedo changed dramatically after 4.0 Gyr of evolution. The sublimation has three important effects on the resultant surface albedo. First, the albedo in the leading hemisphere has significantly decreased to approach the minimum value. Second, the albedo distribution has been elongated along the equator. Third, the edge of the low albedo region has become clear. Considering the effect of ice sublimation, the current albedo distribution can be reconstructed from the sinusoidal albedo distribution, suggesting the apex-antapex cratering asymmetry as a candidate for the origin of the albedo dichotomy. From the model analysis, we obtained an important aspect that the depth of the turn-over layer where the darkening process proceeded for 4 Gyr should be an order of 10 cm, which is consistent with evaluation from the Cassini radar observations. (C) 2011 Elsevier Inc. All rights reserved.

Intermittent cumulonimbus activity breaking the three-layer cloud structure of Jupiter
Sugiyama, K., Nakajima, K., Odaka, M., Ishiwatari, M., Kuramoto, K., Morikawa, Y., Nishizawa, S., Takahashi, Y.O., Hayashi, Y.-Y.
Geophysical Research Letters, 38, 13, L13201, 5 PP., 2011 doi:10.1029/2011GL047878, AMER GEOPHYSICAL UNION, 2011, [Peer-reviewed]
English, Scientific journal, A long-term numerical simulation is performed to investigate idealized characteristics of the cloud layer of Jupiter's atmosphere using a two-dimensional cloud convection model that treats thermodynamics and microphysics of the three cloud components, H(2)O, NH(3), and NH(4)SH. A prominent result obtained is intermittent emergence of vigorous cumulonimbus clouds rising from the H(2)O condensation level to the tropopause. Due to the active transport associated with these clouds, the mean vertical distributions of cloud particles and condensible gases are distinctly different from the hitherto accepted three-layered structure; considerable amounts of H(2)O and NH(4)SH cloud particles exist above the NH(3) condensation level, while the mixing ratios of all condensible gases decrease with height from the H(2)O condensation level. The mean vertical profile of NH(3) vapor is consistent with the results of radio observations in that the abundance of NH(3) is subsolar below the NH(3) cloud base. Citation: Sugiyama, K., K. Nakajima, M. Odaka, M. Ishiwatari, K. Kuramoto, Y. Morikawa, S. Nishizawa, Y. O. Takahashi, and Y.-Y. Hayashi (2011), Intermittent cumulonimbus activity breaking the three-layer cloud structure of Jupiter, Geophys. Res. Lett., 38, L13201, doi: 10.1029/2011GL047878.

「月惑星探査の来たる10年」検討・第一段階報告　　　　　　　　　　　　　　　
大谷栄治, 倉本圭, 今村剛, 寺田直樹, 渡部重十, 荒川政彦, 伊藤孝士, 圦本尚義, 渡部潤一, 木村淳, 高橋幸弘, 中島健介, 中本泰史, 三好由純, 小林憲正, 山岸明彦, 並木則行, 小林直樹, 出村裕英, 大槻圭史
日本惑星科学会誌, 20, 350, 366, 2011, [Peer-reviewed]
Japanese, Scientific journal

上端応力無し, 下端滑り無し条件を課した回転球殻中に出現する弱磁場ダイナモ　　　　　　　　　　　　　　　
佐々木 洋平, 竹広 真一, HAYASHI YOSHIYUKI, 倉本 圭
ながれ 別冊, 29221, 2010
Japanese, Scientific journal

Exploring the Martian meteorology and hydrology
IMAMURA Takeshi, KASAI Yasuko, SAGAWA Hideo, KURODA Takeshi, SATOH Takehiko, UENO Munetaka, SUZUKI Makoto, TAKAHASHI Yukihiro, TAKAHASHI Yoshiyuki, HASHIMOTO George L., KURAMOTO Kiyoshi
Planetary people, 18, 2, 76, 78, The Japanese Society for Planetary Sciences, 25 Jun. 2009
Japanese, 火星表層の水循環や気象学の理解を目的とする火星周回衛星の検討を進めている.可視〜赤外域での高解像度の分光撮像による水蒸気マッピングと大気力学場モニター,そしてサブミリ波サウンダーによる水蒸気やその他微量ガスの3次元分布の観測が,二つの柱である.着陸機による局地気象の直接観測や大気電気観測との連携についても検討中である.

ハビタブル惑星の起源, 進化, 多様性
倉本 圭, 阿部 豊, はしもと じょーじ, 林 祥介, 関根 康人, 佐藤 光輝
天文月報, 102, 3, 184, 189, 日本天文学会, 20 Feb. 2009
Japanese

Collaboration Between University and Public Observatory Based on a Broadband Network
SUGIYAMA Ko-ichiro, ODAKA Masatsugu, SANO Yasuo, OHISHI Norikatsu, BABA Satoshi, TAKAI Yoshiaki, OHISHI Takahisa, HAYASHI Yoshi-Yuki, KURAMOTO Kiyoshi, WATANABE Shigeto
Planetary people, 17, 2, 123, 129, The Japanese Society for Planetary Sciences, 25 Jun. 2008
Japanese, 北海道大学と名寄市立木原天文台とを接続する広帯域ネットワークを構築し,研究と教育の連携のための実験を行った.広帯域ネットワークを用いる最大の利点は,地理的に離れた両拠点の既存の機材とソフトウェア環境を現地まで移動することなく相互に利用できるようになり,両拠点が一体の遠隔天文台として機能できることである.実際に,北海道大学から木原天文台の望遠鏡を遠隔操作して天体の操像観測を試み,遠隔天文台としての機能の検証を行った.また,両拠点の観望映像のどちらか条件の良い映像をインターネット中継映像として配信する実験を行い,今回我々の構築したネットワーク環境が天文現象のインターネット中継の成功率向上に資することを確認した.

Mass-independent oxygen isotope variation in the solar nebula　　　　　　　　　　　　　　　
Young, Edward D, Kuramoto, Kiyoshi, Marcus, Rudolph A, Yurimoto, Hisayoshi, Jacobsen, Stein B
Reviews in Mineralogy and Geochemistry, 68, 1, 187, 218, Mineralogical Society of America, 2008
Scientific journal

氷が担う原始太陽系星雲のグローバル物質輸送　　　　　　　　　　　　　　　
低温科学, 66, 83, 88, 2008

Oxygen isotopic evolution in the early solar nebula: Validation of the H2O transport model
Takashi Fukui, Kiyoshi Kuramoto
ORIGIN OF MATTER AND EVOLUTION OF GALAXIES, 1016, 409, 411, AMER INST PHYSICS, 2008, [Peer-reviewed]
English, International conference proceedings, We perform a numerical simulation on the global transport process of O-16-poor H2O and silicate in a protoplanetary disk to examine whether the process is responsible for the oxygen isotopic systematics observed in chondritic components without conflicting with observation of protoplanetary disks and theory of planet formation.

Enigmas of the lunar thermal evolution
KURAMOTO Kiyoshi, GENDA Hidenori, ARAI Tomoko, OKADA Tatsuaki, SUGITA Seiji
Planetary people, 16, 3, 197, 207, The Japanese Society for Planetary Sciences, 25 Sep. 2007
Japanese, 惑星内部の進化の実証的研究は惑星科学の萌芽的分野であり,「かぐや」をはじめとする月の新たな探査はその前進のための大きな一歩となる.本論文では,これまでの月内部進化についての理解とそれにまっわる謎について,月の熱進化の観点からレビューする.そして今後どのような着眼点で何を調べると月内部進化の理解に有益なのか,考えるためのヒントを提供したい.

Remnants of the early solar system water enriched in heavy oxygen isotopes
Sakamoto, N., Seto, Y., Itoh, S., Kuramoto, K., Fujino, K., Nagashima, K., Krot, A.N., Yurimoto, H.
Science, 317, 5835, 231, 233, AMER ASSOC ADVANCEMENT SCIENCE, 2007, [Peer-reviewed], [International Magazine]
English, Scientific journal, Oxygen isotopic composition of our solar system is believed to have resulted from mixing of two isotopically distinct nebular reservoirs, O-16-rich and O-17,O-18-rich relative to Earth. The nature and composition of the O-17,O-18-rich reservoir are poorly constrained. We report an in situ discovery of a chemically and isotopically unique material distributed ubiquitously in fine-grained matrix of a primitive carbonaceous chondrite Acfer 094. This material formed by oxidation of Fe, Ni-metal and sulfides by water either in the solar nebula or on a planetesimal. Oxygen isotopic composition of this material indicates that the water was highly enriched in O-17 and O-18 (delta O-17,18(SMOW) = + 180 parts per thousand per mil), providing the first evidence for an extremely O-17,O-18-rich reservoir in the early solar system.

Origin and evolution of oxygen isotopic compositions of the solar system
Yurimoto, Hisayoshi, Kuramoto, Kiyoshi, Krot, Alex, er N, Scott, Edward RD, Cuzzi, Jeffrey N, Thiemens, Mark H, Lyons, James R
Protostars and planets V, 849, 862, Citeseer, 2007, [Peer-reviewed]
Scientific journal

Static stability of the Jovian atmospheres estimated from moist adiabatic profiles
Sugiyama, K.-I., Odaka, M., Kuramoto, K., Hayashi, Y.-Y.
Geophysical Research Letters, 33, 3, L03201, L03201, AMER GEOPHYSICAL UNION, 2006, [Peer-reviewed]
English, Scientific journal, The dependency of static stability N-2 of the Jovian atmospheres on the abundances of condensible elements is considered by calculating the moist adiabatic profiles. An optimal minimization method of the Gibbs free energy is utilized to obtain equilibrium compositions in order to cover a variety of basic elements. It is shown that CH4 is one of the dominant contributors to producing a stable layer in the Uranian atmosphere. On Jupiter, R. K. Achterberg and A. P. Ingersoll (1989) have shown that, at low water abundances, N-2 is proportional to the H2O abundance. In the present study, we show that this relationship does not hold when the H2O abundance is larger than approximately 5 x solar. A rough estimation of wave speed indicates that the abundance of 10 x solar is marginal to explain the SL9-induced wave speed as that of an internal gravity wave.

Molecular cloud origin hypothesis for the Oxygen isotopic heterogeneity in the solar system
KURAMOTO Kiyoshi, YURIMOTO Hisayoshi
Planetary people, 14, 4, 193, 200, The Japanese Society for Planetary Sciences, 25 Dec. 2005
Japanese

Oxygen isotopic heterogeneity in the solar system: the molecular cloud origin hypothesis and its implications for meteorites and the planets
Kuramoto Kiyoshi, Yurimoto Hisayoshi
Chondrites and the Protoplanetary Disk, 341, 181, 192, 2005, [Peer-reviewed]

Molecular cloud origin for the oxygen isotope heterogeneity in the solar system
Yurimoto, H., Kuramoto, K.
Science, 305, 5691, 1763, 6, 5691, 2004, [Peer-reviewed], [International Magazine]
English, Scientific journal, Meteorites and their components have anomalous oxygen isotopic compositions characterized by large variations in 18O/16O and 17O/16O ratios. On the basis of recent observations of star-forming regions and models of accreting protoplanetary disks, we suggest that these variations may originate in a parent molecular cloud by ultraviolet photodissociation processes. Materials with anomalous isotopic compositions were then transported into the solar nebula by icy dust grains during the collapse of the cloud. The icy dust grains drifted toward the Sun in the disk, and their subsequent evaporation resulted in the 17O- and 18O-enrichment of the inner disk gas.

An experiment of interactive remote lectures on earth and planetary science connecting a high school with an university
NAKAGAMI Yuuichi, OHSHIMA Osamu, SUGIYAMA Ko-ichiro, KAWABATA Yoshihito, SATO Koichiro, KOBAYASHI Kazumasa, SASAGAWA Hirotatsu, ODAKA Masatsugu, KURAMOTO Kiyoshi, Mosir project
Planetary people, 12, 2, 80, 88, The Japanese Society for Planetary Sciences, 25 Jun. 2003
Japanese

Role of H2O and CO2 ices in martian climate changes
Yokohata, T., Odaka, M., Kuramoto, K.
Icarus, 159, 2, 439, 448, ACADEMIC PRESS INC ELSEVIER SCIENCE, 2002, [Peer-reviewed]
English, Scientific journal, In order to study the stability of martian climate, we constructed a two-dimensional (horizontal-vertical) energy balance model. The long-term CO2 mass exchange process between the atmosphere and CO2 ice caps is investigated with particular attention to the effect of planetary ice distribution on the climate stability. Our model calculation suggests that high atmospheric pressure presumed for past Mars would be unstabilized if H2O ice widely prevailed. As a result, a cold climate state might have been achieved by the condensation of atmospheric CO2 onto ice caps. On the other hand, the low atmospheric pressure, which is buffered by the CO2 ice cap and likely close to the present pressure, would be unstabilized if the CO2 ice albedo decreased. This may have led the climate into a warm state with high atmospheric pressure owing to complete evaporation of CO2 ice cap. Through the albedo feedback mechanisms of H2O and CO2 ices in the atmosphere-ice cap system, Mars may have experienced warm and cold climates episodically in its history. (C) 2002 Elsevier Science (USA).

Thermal evolution of a growing Mars
Hiroki Senshu, Kiyoshi Kuramoto, Takafumi Matsui
Journal of Geophysical Research: Planets, 107, E12, 1, 1, Wiley-Blackwell, 2002
Scientific journal

Climate changes on Mars : CO_2 polar cap and H_2O ice sheet Tokuta
YOKOHATA, KURAMOTO Kiyoshi
Planetary people, 10, 2, 64, 74, The Japanese Society for Planetary Sciences, 25 Jun. 2001
Japanese

Early thermal history of a proto-planet
SENSHU Hiroki, KURAMOTO Kiyoshi, MATSUI Takafumi
Planetary people, 9, 1, 17, 32, The Japanese Society for Planetary Sciences, 25 Mar. 2000
Japanese

エウロパの海　　　　　　　　　　　　　　　
天気 (日本気象学会誌), 47, 39, 40, 2000

水惑星と炭素惑星 (1章 大陸とは何か)
倉本 圭
号外地球, 23, 25, 29, 海洋出版, Feb. 1999
Japanese

鉄のコアの観測可能性　　　　　　　　　　　　　　　
遊・星・人 (日本惑星科学会誌), 7, 218, 220, 1998

Oscillating Magnetic Dipole Moment of Europa Induced by Jovian Magnetic Field: A Possible Probe for Detecting Europa's Ocean
Kuramoto Kiyoshi, Saiganji Yoshihiko, Yamamoto Tetsuo
Lunar and Planetary Science Conference, 29, 1998, [Peer-reviewed]

The Tide is Making
KURAMOTO Kiyoshi
Planetary people, 6, 3, 196, 198, The Japanese Society for Planetary Sciences, 25 Sep. 1997
Japanese

Accretion, core formation, H and C evolution of the Earth and Mars
Kiyoshi Kuramoto
Physics of the Earth and Planetary Interiors, 100, 1-4, 3, 20, Elsevier, 1997
English, Scientific journal, Recent understandings of planetary accretion have suggested that accumulation of a small number of large planetesimals dominates intermediate to final growth stages of the terrestrial planets, with impact velocity high enough to induce extensive melting of the planetesimal and target materials, resulting in formation of a large molten region in which gravitational segregation of silicate and metal, that is, core formation proceeds. In case of homogeneous accretion, volatiles contained in each planetesimal are likely subjected to partitioning among gas, silicate melt, and molten metallic iron at significantly high temperatures and pressures in such a massive molten region. Each phase would subsequently form the proto-atmosphere, -mantle, or -core, respectively. Such chemical reprocessing of H and C associated with core formation, which is followed by both degassing from mantle and atmospheric escape, may result in a diverse range of H2O/CO2 in planetary surface environments, which mainly depends on the H and C content relative to metallic iron in planetary building stones. This may explain inferred difference in volatile distribution between the Earth's (relatively H2O-rich, CO2-poor) and the martian (H2O-poor, CO2-rich) surface environments. Such volatile redistribution may be systematically described by using the retentivity of H2O, ξ, defined as follows: ξ = 1 - ([CO]0 + 2[CH4]0 + 2[C(gr)]0)/[H2O]0, where [i]0 represents mol number of species i partitioned into non-metallic phases, that is, gas and silicate melt in impact-induced molten region. When ξ >
0.5, relatively H2O-rich and CO2-poor surface environment may eventually evolve, although a small portion of H2O partitioned into the non-metallic phases are possibly consumed by subsequent chemical reactions with reduced C-species with producing CO2 and H2. When ξ <
0.5, on the contrary, H2O consumption by the above reactions and selective loss of H2 to space may result in relative H2O-depleted and CO2-rich surface environment. Given the building stone composition by the two-component model by Ringwood (1977) and Wänke (1981), ξ is found to decrease with increasing the mixing fraction of the volatile-rich component: ξ >
0.5 for the mixing fraction smaller than about 15-20% and, ξ <
O for the mixing fraction larger than about 20-30%. This is not significantly dependent on temperature and pressure in molten region and H/C ratio in the building stone. The estimated mixing fraction of the volatile-rich component, about 10% for the Earth and 35% for Mars, is consistent with the observed difference in volatile distribution between the surfaces of both planets. © 1997 Elsevier Science B.V.

Partitioning of H and C between the mantle and core during the core formation in the Earth: Its implications for the atmospheric evolution and redox state of early mantle
Kiyoshi Kuramoto, Takafumi Matsui
Journal of Geophysical Research: Planets, 101, E6, 14909, 14932, Wiley-Blackwell, 01 Jun. 1996, [Peer-reviewed]
English, Scientific journal, Partitioning of H and C among fluid, silicate melt, and molten metallic iron within a growing Earth at temperatures 2000-2500 K and pressures 0.2-5 GPa is estimated by using a thermodynamic model based on the recent knowledge on gas solubility into silicate melts and molten metallic iron. The repulsive interactions among H, C, and S dissolved in molten metallic iron are taken into account. It is shown that partition coefficient of H between molten metallic iron and silicate melt increases with pressure and temperature. Under the presence of Fe-rich metal, CO2 content in silicate melt is suggested to be very low because of low oxygen fugacity under such condition. Assuming a homogeneous accretion of planetesimals with the composition given by the two-component model slightly modified from Ringwood [1977] and Wanke [1981], it is shown that C is preferentially partitioned to molten metallic iron and quite less to silicate melt, whereas a substantial proportion of H is partitioned to silicate melt as H2O and also to molten metallic iron as interstitial atoms. For such concentrations of H, C, and S, the effect of thermodynamic interaction among them in molten metallic iron is not strong enough to cause the oversaturation of graphite. H and C partitioned to molten metallic iron may account for a significant portion of the density deficit in Earth's core. The estimated amount of H2O partitioned to silicate melt is possibly large enough to explain the sources for (1) H2O in the hydrosphere and mantle, (2) oxygen which partially oxidizes ferrous iron to ferric iron in the mantle, and (3) oxidant for metals which may fail to segregate to the core and act as the source of the highly siderophile elements in the mantle of the present Earth. The higher H/C and the lower C/(36) Ar ratios in the silicate Earth including the hydrosphere compared to various classes of meteorites are possibly explained if these elements are derived from the early mantle material after the H and C partitioning to molten metallic iron and core segregation. Accretion of the late veneer material such as the highly oxidized, CI chondrite-like material seems difficult to explain such elemental abundance pattern without invoking unknown large volatile reservoir in the mantle.

地球はなぜ水惑星なのか
倉本 圭, 松井 孝典
科学, 66, 3, 193, 201, 岩波書店, Mar. 1996
Japanese

Partitioning of H and C between the mantle and core during the core formation in the Earth: Its implications for the atmospheric evolution and redox state of early mantle
Kiyoshi Kuramoto, Takafumi Matsui
Journal of Geophysical Research E: Planets, 101, 6, 14909, 14932, American Geophysical Union, 1996
English, Scientific journal, Partitioning of H and C among fluid, silicate melt, and molten metallic iron within a growing Earth at temperatures 2000-2500 K and pressures 0.2-5 GPa is estimated by using a thermodynamic model based on the recent knowledge on gas solubility into silicate melts and molten metallic iron. The repulsive interactions among H, C, and S dissolved in molten metallic iron are taken into account. It is shown that partition coefficient of H between molten metallic iron and silicate melt increases with pressure and temperature. Under the presence of Fe-rich metal, CO2 content in silicate melt is suggested to be very low because of low oxygen fugacity under such condition. Assuming a homogeneous accretion of planetesimals with the composition given by the two-component model slightly modified from Ringwood [1977] and Wänke [1981], it is shown that C is preferentially partitioned to molten metallic iron and quite less to silicate melt, whereas a substantial proportion of H is partitioned to silicate melt as H2O and also to molten metallic iron as interstitial atoms. For such concentrations of H, C, and S, the effect of thermodynamic interaction among them in molten metallic iron is not strong enough to cause the oversaturation of graphite. H and C partitioned to molten metallic iron may account for a significant portion of the density deficit in Earth's core. The estimated amount of H2O partitioned to silicate melt is possibly large enough to explain .the sources for (1) H2O in the hydrosphere and mantle, (2) oxygen which partially oxidizes ferrous iron to ferric iron in the mantle, and (3) oxidant for metals which may fail to segregate to the core and act as the source of the highly siderophile elements in the mantle of the present Earth. The higher H/C and the lower C/36 Ar ratios in the silicate Earth including the hydrosphere compared to various classes of meteorites are possibly explained if these elements are derived from the early mantle material after the H and C partitioning to molten metallic iron and core segregation. Accretion of the late veneer material such as the highly oxidized, CI chondrite-like material seems difficult to explain such elemental abundance pattern without invoking unknown large volatile reservoir in the mantle. Copyright 1996 by the American Geophysical Union.

Earth and Mars : H, C, and Early Differentiation
KURAMOTO Kiyoshi
Planetary People, 4, 4, 201, 214, The Japanese Society for Planetary Sciences, 01 Dec. 1995
Japanese

Formation of a hot proto-atmosphere on the accreting giant icy satellite: implications for the origin and evolution of Titan, Ganymede, and Callisto
Kuramoto, K., Matsui, T.
Journal of Geophysical Research, 99, E10, 21183, 21200, Wiley-Blackwell, 1994
Scientific journal

Fly me to another moon world: Martian Moons eXploration (MMX) (1) - MMX opens new doors -
倉本圭, 倉本圭, 日本惑星科学会誌 遊・星・人, 32, 2, 2023

還元的初期地球大気の光化学的進化
吉田辰哉, 小山俊吾, 中村勇貴, 寺田直樹, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2023, 2023

火星衛星探査計画MMXの進展と科学2023
倉本圭, 倉本圭, 川勝康弘, 藤本正樹, BARUCCI Maria Antonella, 玄田英典, HELBERT Joern, 平田成, 今村剛, 亀田真吾, 亀田真吾, 小林正規, 草野広樹, LAWRENCE David J., 松本晃治, MICHEL Patrick, 宮本英昭, 中川広務, 中村智樹, 小川和律, 大嶽久志, 尾崎正伸, RUSSELL Sara, 佐々木晶, 澤田弘崇, 千秋博紀, 寺田直樹, ULAMEC Stephan, 臼井寛裕, 和田浩二, 横田勝一郎, 日本惑星科学会秋季講演会予稿集(Web), 2023, 2023

PhobosとDeimosの起源:一時捕獲天体のガス抵抗による捕獲
松岡亮, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2023, 2023

Mission Operation Study of Martian Moons eXploration (MOWT)
中村智樹, 池田人, 竹尾洋介, 神山徹, 中川広務, 松本晃治, 千秋博紀, 亀田真吾, 寺田直樹, 岩田隆浩, 横田勝一郎, 尾崎直哉, 平田成, 宮本英昭, 小川和律, 草野広樹, 小林正規, 大木優介, BARUCCI Antonietta, SAWYER Eric, LAWRENCE David J., CHABOT Nancy L., PEPLOWSKI Patrick N., ULAMEC Stephan, MICHEL Patrick, 今田高峰, 今井茂, 石田初美, 尾川順子, 倉本圭, 安光亮一郎, 大嶽久志, 川勝康弘, 宇宙科学技術連合講演会講演集(CD-ROM), 67th, 2023

New views on the science background of Martian Moons eXploration MMX
倉本圭, 倉本圭, 川勝康弘, 宇宙科学技術連合講演会講演集(CD-ROM), 67th, 2023

Martian Moons eXploration (MMX), Overview and Development Status
川勝康弘, 倉本圭, 大嶽久志, 今田高峰, 馬場肇, 宇宙科学技術連合講演会講演集(CD-ROM), 67th, 2023

Pre-arrival Landing Site Selection for the Martian Moons eXploration (MMX)
和田浩二, 中村智樹, 宮本英昭, 松本晃治, 平田成, 菊地紘, 逸見良道, 清水俊輔, 菊地翔太, 森田朋代, 小林真輝人, 清水雄太, 竹村知洋, VARSHA Natarajan, 堀田啓貴, 平田直之, 松岡萌, 巽瑛理, 黒川宏之, 長勇一郎, 田畑陽久, 倉本圭, 諸田智克, 永峰健太, 大槻真嗣, 馬場満久, 小川和律, 巳谷真司, 岡田尚基, 尾川順子, 池田人, 竹尾洋介, 松本祐樹, 大野剛, 吉川健人, 安光亮一郎, 宇宙科学技術連合講演会講演集(CD-ROM), 67th, 2023

原始地球大気海洋系でのNH₃の持続時間
有馬銀河, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2022, 2022

M型矮星ハビタブルゾーン内に存在するGJ832cは水素大気を持つか
長野剛流, 吉田辰哉, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2022, 2022

火星衛星探査計画MMXの進展と科学2022
倉本圭, 倉本圭, 川勝康弘, 藤本正樹, BARUCCI Maria Antonella, 玄田英典, HELBERT Joern, 平田成, 今村剛, 亀田真吾, 亀田真吾, 小林正規, 草野広樹, LAWRENCE David J., 松本晃治, MICHEL Patrick, 宮本英昭, 中川広務, 中村智樹, 小川和律, 大嶽久志, 尾崎正伸, RUSSELL Sara, 佐々木晶, 澤田弘崇, 千秋博紀, 寺田直樹, ULAMEC Stephan, 臼井寛裕, 和田浩二, 横田勝一郎, 日本惑星科学会秋季講演会予稿集(Web), 2022, 2022

原始火星マントル・コアに分配される揮発性成分
齊藤大晶, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2022, 2022

Mission Operation Study of Martian Moons eXploration (MOWT)
竹尾洋介, 中村智樹, 池田人, 神山徹, 中川広務, 松本晃治, 千秋博紀, 亀田真吾, 寺田直樹, 岩田隆浩, 横田勝一郎, 尾崎直哉, GONZALEZ-FRANQUESA Ferran, 平田成, 宮本英昭, 小川和律, 草野広樹, 小林正規, 大木優介, BARESI Nicola, BARUCCI Antonietta, SAWYER Eric, LAWRENCE David J., CHABOT Nancy L., PEPLOWSKI Patrick N., ULAMEC Stephan, MICHEL Patrick, 今田高峰, 今井茂, 石田初美, 尾川順子, 倉本圭, 安光亮一郎, 大嶽久志, 川勝康弘, 宇宙科学技術連合講演会講演集(CD-ROM), 66th, 2022

Overview of Sciences of Martian Moons eXproration MMX
倉本圭, 倉本圭, 川勝康弘, 宇宙科学技術連合講演会講演集(CD-ROM), 66th, 2022

Status of study on the spacecraft candidate landing regions for the Martian Moons eXploration (MMX)
和田浩二, 中村智樹, 宮本英昭, 松本晃治, 平田成, 菊地紘, 逸見良道, 清水俊輔, 菊地翔太, 倉本圭, 諸田智克, 小川和律, 巳谷真司, 岡田尚基, 尾川順子, 池田人, 竹尾洋介, 松本祐樹, 大野剛, 吉川健人, 安光亮一郎, 宇宙科学技術連合講演会講演集(CD-ROM), 66th, 2022

Martian Moons eXploration (MMX), Overview and Development Status
川勝康弘, 倉本圭, 大嶽久志, 今田高峰, 馬場肇, 宇宙科学技術連合講演会講演集(CD-ROM), 66th, 2022

4個の小惑星の偏光観測の再解析によるデータ改善と分光分類との比較
匠あさみ, 匠あさみ, 渡部潤一, 大坪貴文, 古荘玲子, 古荘玲子, 臼井文彦, 臼井文彦, 川端弘治, 中岡竜也, 山中雅之, 川端美穂, 石黒正晃, 倉本圭, 今井正尭, 大野辰遼, 渡邉誠, 日本天文学会年会講演予稿集, 2022, 2022

火星衛星探査計画MMXとシミュレーション天文学
倉本圭, 日本天文学会年会講演予稿集, 2021, 2021

金星大気の放射計算と放射対流平衡実験
高橋芳幸, はしもと じょーじ, 石渡正樹, 倉本圭, 樫村博基, 林祥介, 日本気象学会大会講演予稿集(CD-ROM), 120, 2021

Internal heating of icy ocean worlds
鎌田俊一, 中西健人, 倉本圭, 日本地球惑星科学連合大会予稿集(Web), 2021, 2021

Oceanic retention of ammonia and thermal stability of the atmosphere-ocean system on the primitive earth
有馬銀河, 倉本圭, 日本地球惑星科学連合大会予稿集(Web), 2021, 2021

Numerical calculation of moist convection in Jupiter’s atmosphere-A case study with an average cooling vertical profile based on a radiative transfer calculation-
関口太郎, 杉山耕一朗, 石渡正樹, 中島健介, 倉本圭, 林祥介, 林祥介, 日本地球惑星科学連合大会予稿集(Web), 2021, 2021

木星の雲対流の数値計算~放射伝達計算による平均冷却鉛直分布を与えた場合~
関口太郎, 杉山耕一朗, 石渡正樹, 中島健介, 倉本圭, 林祥介, 日本気象学会大会講演予稿集(CD-ROM), 119, 2021

火星サイズの原始惑星内部に分配される揮発性成分量
齊藤大晶, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2021, 2021

原始地球におけるNH₃の海洋への貯蔵と大気海洋系での熱的安定性
有馬銀河, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2021, 2021

火星衛星探査計画MMX:詳細設計段階における科学検討の深化
倉本圭, 倉本圭, 川勝康弘, 藤本正樹, BARUCCI Maria Antonella, 玄田英典, HELBERT Joern, 平田成, 今村剛, 亀田真吾, 小林正規, 草野広樹, LAWRENCE David J., 松本晃治, MICHEL Patrick, 宮本英昭, 中川広務, 中村智樹, 小川和律, 小川和律, 大嶽久志, 尾崎正伸, RUSSELL Sara, 佐々木晶, 澤田弘崇, 千秋博紀, 寺田直樹, ULAMEC Stephan, 臼井寛裕, 和田浩二, 横田勝一郎, 日本惑星科学会秋季講演会予稿集(Web), 2021, 2021

Study of Landing Sites Selection for the Martian Moons eXploration (MMX)
和田浩二, 中村智樹, 宮本英昭, 松本晃治, 平田成, 菊地紘, 逸見良道, 菊地翔太, 倉本圭, 小川和律, 巳谷真司, 岡田尚基, 尾川順子, 池田人, 竹尾洋介, 宇宙科学技術連合講演会講演集(CD-ROM), 65th, 2021

Mission Operation Study of Martian Moons eXploration (MOWT)
中村智樹, 池田人, 竹尾洋介, 神山徹, 中川広務, 松本晃治, 千秋博紀, 亀田真吾, 寺田直樹, 岩田隆浩, 横田勝一郎, 尾崎直哉, GONZALEZ-FRANQUESA Ferran, 平田成, 宮本英昭, 小川和律, 草野広樹, 小林正規, 大木優介, BARESI Nicola, BARUCCI Antonietta, SAWYER Eric, LAWRENCE David J., CHABOT Nancy L., PEPLOWSKI Patrick N., ULAMEC Stephan, MICHEL Patrick, 今田高峰, 今井茂, 石田初美, 尾川順子, 倉本圭, 安光亮一郎, 大嶽久志, 川勝康弘, 宇宙科学技術連合講演会講演集(CD-ROM), 65th, 2021

Martian Moons eXploration (MMX), Overview and Mission Scenario
川勝康弘, 倉本圭, 大嶽久志, 今田高峰, 馬場肇, 宇宙科学技術連合講演会講演集(CD-ROM), 65th, 2021

A status report: MMX curation activity
臼井寛裕, 菅倉春菜, 倉本圭, 倉本圭, 川勝康弘, 宇宙科学技術連合講演会講演集(CD-ROM), 65th, 2021

Sciences of Martian Moons eXproration MMX
倉本圭, 倉本圭, 川勝康弘, 宇宙科学技術連合講演会講演集(CD-ROM), 65th, 2021

Participation of Japanese planetary science community to the Mercury exploration mission BepiColombo
鎌田俊一, 兵頭龍樹, 高橋太, 吉崎昂, 石城陽太, 倉本圭, 村上豪, 藤本正樹, 日本地球惑星科学連合大会予稿集(Web), 2020, 2020

星雲ガス中で集積する岩石惑星の希ガス同位体比
齊藤大晶, 馬上謙一, 山本順司, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2020, 2020

還元型原始地球大気の流体力学的散逸
吉田辰哉, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2020, 2020

日欧共同BepiColombo水星探査計画に向けた取り組み:水星形成解明のための理論研究
鎌田俊一, 兵頭龍樹, 高橋太, 吉崎昂, 石城陽太, 倉本圭, 村上豪, 日本惑星科学会秋季講演会予稿集(Web), 2020, 2020

Martian moon formation scenario with capture of moon precursors and their accretion in the circum-Mars region
松岡亮, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2020, 2020

凝結性成分による対流抑制条件を念頭においた木星型惑星の雲対流の数値計算
杉山耕一朗, 中島健介, 倉本圭, 林祥介, 林祥介, 日本気象学会大会講演予稿集(CD-ROM), 117, 2020

Inhibition of moist convection in the atmospheres of Jovian planets: the case of NH4SH formation by chemical reaction of NH3 and H2S
杉山耕一朗, 中島健介, 倉本圭, 林祥介, 日本地球惑星科学連合大会予稿集(Web), 2020, 2020

火星衛星探査計画MMXの進捗
倉本圭, 倉本圭, 川勝康弘, 藤本正樹, BARUCCI Maria Antonella, LAWRENCE David J., 玄田英典, 平田成, 今村剛, 亀田真吾, 小林正規, 草野広樹, 松本晃治, MICHEL Patrick, 宮本英昭, 中川広務, 中村智樹, 小川和律, 小川和律, 大嶽久志, 尾崎正伸, RUSSEL Sara, 佐々木晶, 澤田弘崇, 千秋博紀, 寺田直樹, ULAMEC Stephan, 臼井寛裕, 和田浩二, 横田勝一郎, 日本惑星科学会秋季講演会予稿集(Web), 2020, 2020

Overview and Exploration Scenario of Martian Moons eXploration (MMX)
川勝康弘, 倉本圭, 大嶽久志, 今田高峰, 馬場肇, 宇宙科学技術連合講演会講演集(CD-ROM), 64th, 2020

Science by the Martian Moon eXploration MMX
倉本圭, 川勝康弘, 宇宙科学技術連合講演会講演集(CD-ROM), 64th, 2020

A Pan of MMX Science Board Activity for the Production of Science Output
臼井寛裕, 倉本圭, 倉本圭, 和田浩二, 川勝康弘, 宇宙科学技術連合講演会講演集(CD-ROM), 64th, 2020

The Atmosphere of Aqua-planet Earth : Its Vertical Structure and Interactions with Space
KURAMOTO Kiyoshi, Vacuum and Surface Science, 63, 4, 171, 176, 2020

A planetary atmosphere is the gaseous layer that divides the planetary surface and surrounding space. Although the Earth's atmosphere occupies a tiny fraction of the total Earth's mass, it plays an essential role to make the Earth's surface environment circulating liquid-water that is thought to be the most fundamental condition for the emergence and evolution of the terrestrial life organisms. The vertical structure of Earth's atmosphere from the Earth's surface to the uppermost region that merges into space is strongly influenced by interactions with space.

, The Japan Society of Vacuum and Surface Science, Japanese

Jupiter's wind bands have deep roots
グラント アンドリュー, 倉本 圭, パリティ = Parity : 物理科学雑誌, 34, 4, 40, 43, Apr. 2019
丸善出版, Japanese

大気大循環モデルを用いた系外惑星の光度曲線解析による自転軸傾斜角推定 II
中川雄太, 小玉貴則, 石渡正樹, 河原創, 須藤靖, 高橋芳幸, はしもと じょーじ, 倉本圭, 中島健介, 竹広真一, 林祥介, 日本天文学会年会講演予稿集, 2019, 2019

NH₄SH生成反応による対流抑制条件を念頭においた木星型惑星の雲対流の数値計算
杉山耕一朗, 中島健介, 倉本圭, 林祥介, 林祥介, 日本惑星科学会秋季講演会予稿集(Web), 2019, 2019

Overview of Martian Moons eXploration (MMX)
川勝康弘, 倉本圭, 大嶽久志, 今田高峰, 馬場肇, 宇宙科学技術連合講演会講演集(CD-ROM), 63rd, 2019

Science of the Martian Moon eXploration MMX
倉本圭, 川勝康弘, 宇宙科学技術連合講演会講演集(CD-ROM), 63rd, 2019

火星衛星探査計画MMX:目指す科学とその推進
倉本圭, 倉本圭, 川勝康弘, 藤本正樹, BIBRING Jean Pierre, LAWRENCE David, 玄田英典, 平田成, 今村剛, 亀田真吾, 松本晃治, 宮本英昭, 諸田智克, 長岡央, 中川広務, 中村智樹, 小川和律, 大嶽久志, 尾崎正伸, 佐々木晶, 千秋博紀, 橘省吾, 橘省吾, 寺田直樹, 臼井寛裕, 和田浩二, 渡邊誠一郎, 日本地球惑星科学連合大会予稿集(Web), 2019, 2019

火星衛星探査計画MMXの進展とサイエンス
倉本圭, 倉本圭, 川勝康弘, 藤本正樹, BIBRING Jean-Pierre, 玄田英典, 平田成, 今村剛, 亀田真吾, LAWRENCE David, 松本晃治, 宮本英昭, 諸田智克, 長岡央, 中川広務, 中村智樹, 小川和律, 大嶽久志, 尾崎正伸, 佐々木晶, 千秋博紀, 橘省吾, 寺田直樹, 臼井寛裕, 和田浩二, 渡邊誠一郎, 日本惑星科学会秋季講演会予稿集(Web), 2019, 2019

Polarimetry of (155140) 2005 UD: the Dynamical Association with (3200) Phaethon
ISHIGURO Masateru, GEEM Jooyeon, NAITO Hiroyuki, BACH Yoonsoo P, KURODA Daisuke, ONO Tatsuharu, TAKAGI Seiko, SATO Mitsuteru, KURAMOTO Kiyoshi, SEKIGUCHI Tomohiko, IMAI Masataka, WATANABE Makoto, OHTSUKA Katsuhito, HASEGAWA Sunao, ITO Takashi, YOSHIDA Fumi, ARAI Tomoko, 日本地球惑星科学連合大会予稿集(Web), 2019, ROMBUNNO.PPS03‐P17 (WEB ONLY), 2019
English

Polarimetric Study of Asteroids in Comet‐Like Orbits (ACOs)
GEEM Jooyeon, ISHIGURO Masateru, BACH Yoonsoo P, KURODA Daisuke, NAITO Hiroyuki, HANAYAMA Hidekazu, KIM Yoonyoung, KWON Yuna G, JIN Sunho, SEKIGUCHI Tomohiko, OKAZAKI Ryo, VAUBAILLON Jeremie J, IMAI Masataka, OONO Tatsuharu, FUTAMUTS Yuki, TAKAGI Seiko, SATO Mitsuteru, KURAMOTO Kiyoshi, WATANABE Makoto, 日本地球惑星科学連合大会予稿集(Web), 2019, ROMBUNNO.PPS03‐P04 (WEB ONLY), 2019
English

Our changing view of Mars
ベイサベーダ アシュイン, 倉本 圭, パリティ = Parity : 物理科学雑誌, 33, 2, 22, 30, Feb. 2018
丸善出版, Japanese

火星衛星の捕獲起源論-回転原始大気による微惑星捕獲と衛星軌道進化-
松岡亮, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2018, 2018

古火星における温室効果気体リサーチ:過酸化水素の影響
伊藤祐一, 倉本圭, はしもと じょーじ, 高橋芳幸, 石渡正樹, 日本惑星科学会秋季講演会予稿集(Web), 2018, 2018

Ganymede Laser Altimeter (GALA) for the JUICE mission-Overview and Japanese development status
塩谷圭吾, 塩谷圭吾, 並木則行, 並木則行, 小林正規, 木村淳, 荒木博志, 荒木博志, 野田寛大, 野田寛大, 田澤誠一, 押上祥子, 鹿島伸悟, 宇都宮真, 石橋高, 小林進悟, 山脇敏彦, 東原和行, 尾崎正伸, 尾崎正伸, 水野貴秀, 水野貴秀, 斎藤義文, 鎌田俊一, 松本晃治, 松本晃治, 佐々木晶, 倉本圭, 佐藤祐貴, 畠山千尋, 横沢剛, 小島健太郎, 水野博行, 谷本和夫, 中川寛之, 今井久人, 桐野宙治, 岩村哲, 藤代尚文, 飯田光人, 松本吉昭, 藤井雅之, LINGENAUBER Kay, ALTHAUS Christian, DEL TOGNO Simone, JAENCHEN Judit, BORGS Belinda, BEHNKE Thomas, LOETZKE Horst-Georg, MICHAELIS Harald, KALLENBACH Reinald, HUSSMANN Hauke, 日本惑星科学会秋季講演会予稿集(Web), 2018, 2018

還元型原始火星大気の流体力学的散逸
吉田辰哉, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2018, 2018

集積末期の地球マントルの酸化還元状態:深いマグマオーシャンにおける第二鉄生成
村瀬祐太郎, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2018, 2018

木星型惑星を想定した雲対流の数値計算~凝結性成分が多いケース~
杉山耕一朗, 中島健介, 小高正嗣, 倉本圭, 林祥介, 日本地球惑星科学連合大会予稿集(Web), 2018, 2018

Overview of Martian Moons eXploration (MMX)
川勝康弘, 倉本圭, 大嶽久志, 今田高峰, 馬場肇, 宇宙科学技術連合講演会講演集(CD-ROM), 62nd, 2018

Science of Martian moons exploration MMX and its mission instruments
倉本圭, 倉本圭, 川勝康弘, 宇宙科学技術連合講演会講演集(CD-ROM), 62nd, 2018

火星衛星探査計画MMXとそのサイエンス2018
倉本圭, 倉本圭, 川勝康弘, 藤本正樹, 玄田英典, 平田成, 今村剛, 亀田真吾, 松本晃治, 宮本英昭, 諸田智克, 長岡央, 中川広務, 中村智樹, 小川和律, 大嶽久志, 尾崎正伸, 佐々木晶, 千秋博紀, 橘省吾, 寺田直樹, 臼井寛裕, 和田浩二, 渡邊誠一郎, 日本惑星科学会秋季講演会予稿集(Web), 2018, 2018

2016年秋の(3200)Phaethon偏光観測結果
伊藤孝士, 石黒正晃, 荒井朋子, 今井正尭, 関口朋彦, BACH Yoonsoo P., KWON Yuna G., 小林正規, 石丸亮, 内藤博之, 渡辺誠, 倉本圭, 日本地球惑星科学連合大会予稿集(Web), 2018, 2018

C型小惑星(74)Galateaの偏光観測
匠あさみ, 匠あさみ, 渡部潤一, 古荘玲子, 古荘玲子, 臼井文彦, 大坪貴文, 川端弘治, 山中雅之, 中岡竜也, 川端美穂, 石黒正晃, 倉本圭, 渡辺誠, 今井正尭, 大野辰遼, 日本天文学会年会講演予稿集, 2018, 2018

Development of a radiative transfer model for planetary atmospheres: Application for Venus atmosphere
TAKAHASHI Yoshiyuki O, ONISHI Masanori, HASHIMOTO George, KURAMOTO Kiyoshi, ISHIWATARI Masaki, TAKAHASHI Yasuto, HAYASHI Yoshi‐Yuki, 日本地球惑星科学連合大会予稿集(Web), 2018, ROMBUNNO.PPS04‐P01 (WEB ONLY), 2018
English

Evolution of D/H ratios on rocky proto‐planets growing in the solar nebula
SAITO Hiroaki, KURAMOTO Kiyoshi, 日本地球惑星科学連合大会予稿集(Web), 2018, ROMBUNNO.MIS18‐13 (WEB ONLY), 2018
English

Polarimetric research on S‐ and Q‐type Near‐Earth Asteroids
GEEM Jooyeon, ISHIGURO Masateru, BACH Yoonsoo P, KURODA Daisuke, NAITO Hiroyuki, KIM Yoonyoung, KWON Yuna G, IMAI Masataka, KURAMOTO Kiyoshi, WATANABE Makoto, OKAZAKI Ryo, 日本地球惑星科学連合大会予稿集(Web), 2018, ROMBUNNO.PPS03‐03 (WEB ONLY), 2018
English

Radiative transfer calculation for various planetary atmospheres
TAKAHASHI Yoshiyuki O, ONISHI Masanori, HASHIMOTO George, KURAMOTO Kiyoshi, ISHIWATARI Masaki, TAKAHASHI Yasuto, HAYASHI Yoshi‐Yuki, 日本地球惑星科学連合大会予稿集(Web), 2018, ROMBUNNO.MGI28‐P06 (WEB ONLY), 2018
English

Martian Moon’s Exploration MMX as a mission revealing the formation of habitable planets
KURAMOTO Kiyoshi, KAWAKATSU Yasuhiro, FUJIMOTO Masaki, GENDA Hidenori, IMAMURA Takeshi, KAMEDA Shingo, MATSUMOTO Koji, MIYAMOTO Hideaki, MOROTA Tomokatsu, NAGAOKA Hiroshi, NAKAMURA Tomoki, OGAWA Kazunori, OTAKE Hisashi, OZAKI Masanobu, SASAKI Sho, SENSHU Hiroki, TACHIBANA Shogo, TERADA Naoki, USUI Tomohiro, WADA Koji, WATANABE Sei‐ichiro, 日本地球惑星科学連合大会予稿集(Web), 2018, ROMBUNNO.PPS08‐09 (WEB ONLY), 2018
English

Meeting on master plan proposals
Nakamoto T., Kuramoto K., Sekine Y., Planetary People - The Japanese Society for Planetary Sciences, 27, 4, 341, 343, 2018
The Japanese Society for Planetary Sciences, Japanese

惑星大気大循環モデルのための放射伝達モデルの構築
高橋芳幸, 大西将徳, はしもと じょーじ, 倉本圭, 石渡正樹, 高橋康人, 林祥介, 日本気象学会大会講演予稿集, 112, 209, 30 Sep. 2017
Japanese

地球大気形成論の新展開
倉本圭, 日本気象学会大会講演予稿集, 112, 206, 30 Sep. 2017
Japanese

火星衛星サンプルリターン計画Martian Moons eXploration
尾崎正伸, 大嶽久志, 川勝康弘, 藤本正樹, 倉本圭, 橘省吾, 寺田直樹, 中村智樹, 和田浩二, 千秋博紀, 宮本英昭, 今村剛, 臼井寛裕, 玄田英典, 亀田真吾, 長岡央, 松本晃治, 諸田智克, 渡邊誠一郎, 佐々木晶, 小川和律, 日本天文学会年会講演予稿集, 2017, 225, 28 Feb. 2017
Japanese

星雲ガス中で集積する岩石惑星内部のD/H
齊藤大晶, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2017, 2017

Ganymede Laser Altimeter (GALA) for the JUICE mission -Overview and Japanese development status
塩谷圭吾, 塩谷圭吾, 並木則行, 並木則行, 小林正規, 木村淳, 荒木博志, 荒木博志, 野田寛大, 野田寛大, 田澤誠一, 押上祥子, 鹿島伸悟, 宇都宮真, 石橋高, 小林進悟, 山脇敏彦, 東原和行, 尾崎正伸, 尾崎正伸, 水野貴秀, 水野貴秀, 斎藤義文, 鎌田俊一, 松本晃治, 松本晃治, 佐々木晶, 倉本圭, 藤井雅之, 横沢剛, 畠山千尋, 佐藤真衣, 小島健太郎, 松井直樹, 中川寛之, 桐野宙治, 岩村哲, 藤代尚文, 飯田光人, 松本吉昭, LINGENAUBER Kay, ALTHAUS Christian, DEL TOGNO Simone, JANCHEN Judit, BORGS Belinda, BEHNKE Thomas, LOETZKE Horst-Georg, MICHAELIS Harald, KALLENBACH Reinald, HUSSMANN Hauke, 日本惑星科学会秋季講演会予稿集(Web), 2017, 2017

放射冷却が原始火星大気の流体力学的散逸に与える影響
吉田辰哉, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2017, 2017

水惑星学の創成
関根康人, 渋谷岳造, 玄田英典, 福士圭介, 臼井寛裕, 高橋嘉夫, 倉本圭, 鍵裕之, 渡邊誠一郎, 日本惑星科学会秋季講演会予稿集(Web), 2017, 2017

TRAPPIST-1系地球型惑星からの水蒸気大気の流体力学的散逸
渡辺健介, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2017, 2017

火星衛星探査計画MMXとそのサイエンス2017
倉本圭, 川勝康弘, 藤本正樹, 玄田英典, 今村剛, 亀田真吾, 松本晃治, 宮本英昭, 諸田智克, 中村智樹, 小川和律, 尾崎正伸, 佐々木晶, 千秋博紀, 橘省吾, 寺田直樹, 臼井寛裕, 和田浩二, 渡邊誠一郎, 日本惑星科学会秋季講演会予稿集(Web), 2017, 2017

Science objectives of the GAnymede Laser Altimeter (GALA) onboard JUICE spacecraft
木村淳, 鎌田俊一, 松本晃治, 松本晃治, 押上祥子, 並木則行, 並木則行, 倉本圭, 佐々木晶, 塩谷圭吾, 塩谷圭吾, 小林正規, 小林進悟, 荒木博志, 荒木博志, 野田寛大, 野田寛大, 石橋高, 齋藤義文, 日本惑星科学会秋季講演会予稿集(Web), 2017, 2017

JUICE/GALA‐J(2):JUICE搭載ガニメデレーザ高度計(GALA)が木星氷衛星で目指す科学
木村淳, 鎌田俊一, 松本晃治, 押上祥子, 並木則行, 倉本圭, 佐々木晶, 塩谷圭吾, 小林正規, 小林進悟, 荒木博志, 野田寛大, 石橋高, 斎藤義文, HUSSMANN Hauke, LINGENAUBER Kay, 日本地球惑星科学連合大会予稿集(Web), 2017, ROMBUNNO.PPS07‐P01 (WEB ONLY), 2017
Japanese

Martian Moons eXploration (MMX) Overview
川勝康弘, 倉本圭, 大嶽久志, 宇宙科学技術連合講演会講演集(CD-ROM), 61st, ROMBUNNO.1G01, 2017
Japanese

Scientific Objectives and Payloads for Martian Moons Exploration MMX
草野広樹, 川勝康弘, 倉本圭, 宇宙科学技術連合講演会講演集(CD-ROM), 61st, ROMBUNNO.1G06, 2017
Japanese

Observation of near‐earth object (1566) Icarus and the split candidate 2007 MK6
URAKAWA Seitaro, OHTSUKA Katsutoshi, ABE Shinsuke, KINOSHITA Daisuke, HANAYAMA Hidekazu, MIYAJI Takeshi, OKUMURA Shin‐ichiro, AYANI Kazuya, MAENO Syouta, KURODA Daisuke, FUKUI Akihiko, NARITA Norio, NARITA Norio, NARITA Norio, HASHIMOTO George, SAKURAI Yuri, NAKAMURA Sayuri, TAKAHASHI Jun, TANIGAWA Tomoyasu, BURHONOV Otabek, ERGASHEV Kamoliddin, ITO Takashi, YOSHIDA Fumi, WATANABE Makoto, IMAI Masataka, KURAMOTO Kiyoshi, SEKIGUCHI Tomohiko, ISHIGURO Masateru, 日本地球惑星科学連合大会予稿集(Web), 2017, ROMBUNNO.PPS07‐P07 (WEB ONLY), 2017
English

Martian Moons eXploration (MMX): connecting small bodies with habitable planets
KURAMOTO Kiyoshi, KAWAKATSU Yasuhiro, FUJIMOTO Masaki, GENDA Hidenori, IMAMURA Takeshi, KAMEDA Shingo, MATSUMOTO Koji, MIYAMOTO Hideaki, MOROTA Tomokatsu, NAGAOKA Hiroshi, NAKAMURA Tomoki, OGAWA Kazunori, OTAKE Hisashi, OZAKI Masanobu, SASAKI Sho, SENSHU Hiroki, TACHIBANA Shogo, TERADA Naoki, USUI Tomohiro, WADA Koji, WATANABE Sei‐ichiro, 日本地球惑星科学連合大会予稿集(Web), 2017, ROMBUNNO.PPS02‐30 (WEB ONLY), 2017
English

Polarimetric Study of (331471) 1984 QY1, a Potential Dormant Comet Candidate
KIM Jooyeon, ISHIGURO Masateru, BACH Yoonsoo Park, KURODA Daisuke, NAITO Hiroyuki, KWON Yuna Grace, KIM Yoonyoung, IMAI Masataka, KURAMOTO Kiyoshi, WATANABE Makoto, 日本地球惑星科学連合大会予稿集(Web), 2017, ROMBUNNO.PPS02‐P07 (WEB ONLY), 2017
English

Book review
Kuramoto K., Planetary People - The Japanese Society for Planetary Sciences, 26, 1, 35, 35, 2017
The Japanese Society for Planetary Sciences, Japanese

aqua planetology
Sekine Yasuhito, Shibuya Takazo, Genda Hidenori, Fukushi Keisuke, Usui Tomohiro, Takahashi Yoshio, Kuramoto Kiyoshi, Kagi Hiroyuki, Watanabe Sei―ichiro, Abstracts of Annual Meeting of the Geochemical Society of Japan, 64, 0, 139, 139, 2017

, GEOCHEMICAL SOCIETY OF JAPAN, Japanese

Report of the 5th Workshop on Satellite Systems
Tanigawa Takayuki, Kimura Jun, Okuzumi Satoshi, Sekine Yasuhito, Kuramoto Kiyoshi, Ohtsuki Keiji, Tanaka Hidekazu, Planetary People - The Japanese Society for Planetary Sciences, 26, 4, 190, 191, 2017
The Japanese Society for Planetary Sciences, Japanese

水星の材料物質の起源,熱史,および磁場生成
倉本圭, 木村淳, 佐々木洋平, 宇宙航空研究開発機構特別資料 JAXA-SP-(Web), 16-003, 215‐217 (WEB ONLY), 30 Sep. 2016
Japanese

Scientific Instruments of the Martian Moon Explorer
尾崎正伸, 大嶽久志, 白石浩章, 藤本正樹, 早川基, 川勝康弘, 津田雄一, 今田高峰, 巳谷真司, 三桝裕也, 嶋田貴信, 尾川順子, 渡邊誠一郎, 倉本圭, 宇宙科学技術連合講演会講演集(CD-ROM), 60, 4p, 06 Sep. 2016
日本航空宇宙学会, Japanese

Science of Mars Moons Exploration mission
倉本圭, 藤本正樹, 玄田英典, 今村剛, 亀田真吾, 川勝康弘, 松本晃治, 三桝裕也, 宮本英昭, 諸田智克, 中村智樹, 小川和律, 尾崎正伸, 澤田弘崇, 橘省吾, 寺田直樹, 臼井寛裕, 和田浩二, 渡邊誠一郎, 宇宙科学技術連合講演会講演集(CD-ROM), 60, 5p, 06 Sep. 2016
日本航空宇宙学会, Japanese

地球近傍小天体(1566)Icarus・2007MK₆の観測キャンペーン
浦川聖太郎, 大塚勝仁, 阿部新助, 木下大輔, 黒田大介, 福井暁彦, 花山秀和, 宮地竹史, 成田憲保, はしもと じょーじ, 櫻井友里, 高橋隼, 谷川智康, 綾仁一哉, 前野将太, 石黒正晃, 今井正尭, 倉本圭, 渡辺誠, 関口朋彦, 日本天文学会年会講演予稿集, 2016, 79, 20 Aug. 2016
Japanese

Origin and evolution of Mars to be explored by MMX
Kuramoto Kiyoshi, MMX science study team, 第49回月・惑星シンポジウム = Proceedings of the 49th ISAS Lunar and Planetary Symposium, Jul. 2016
49th ISAS Lunar and Planetary Symposium (July 20-21, 2016. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS), Japanese

Line‐by‐line放射計算による湿潤大気の2つの圏界面レジーム
大西将徳, はしもと じょーじ, 倉本圭, 高橋芳幸, 石渡正樹, 高橋康人, 林祥介, 日本気象学会大会講演予稿集, 109, 81, 30 Apr. 2016
Japanese

JUICE/GALA-J (1): Ganymede Laser Altimeter (GALA) for the JUICE mission-Introduction, current status, and role of the Japan team
塩谷圭吾, 塩谷圭吾, 並木則行, 並木則行, 小林正規, 木村淳, 荒木博志, 荒木博志, 野田寛大, 野田寛大, 押上祥子, 鹿島伸悟, 宇都宮真, 石橋高, 小林進悟, 尾崎正伸, 尾崎正伸, 水野貴秀, 水野貴秀, 斎藤義文, 東原和行, 山脇敏彦, 鎌田俊一, 松本晃治, 松本晃治, 倉本圭, 佐々木晶, 岩村哲, 飯田光人, 松本吉昭, 藤井雅之, 藤井雅之, 藤代尚文, 山室智康, LINGENAUBER Kay, BEHNKE Thomas, OBERST Juergen, JAENCHEN Judit, LOETZKE Horst-Georg, MICHAELIS Harald, HUSSMANN Hauke, 日本惑星科学会秋季講演会予稿集(Web), 2016, 2016

水星の材料物質の起源,熱史,および磁場生成
倉本圭, 木村淳, 佐々木洋平, 宇宙航空研究開発機構特別資料 JAXA-SP-(Web), 16-003, 2016

火星衛星探査ミッションとそのサイエンス
倉本圭, 藤本正樹, 玄田英典, 今村剛, 亀田真吾, 川勝康弘, 松本晃治, 三桝裕也, 宮本英昭, 諸田智克, 中村智樹, 小川和律, 尾崎正伸, 澤田弘崇, 橘省吾, 寺田直樹, 臼井寛裕, 和田浩二, 渡邊誠一郎, 日本惑星科学会秋季講演会予稿集(Web), 2016, 2016

地球近傍小天体Icarusとその同一起源候補天体2007MK6の観測
浦川聖太郎, 大塚勝仁, 阿部新助, 木下大輔, 花山秀和, 宮地竹史, 奥村真一郎, 綾仁一哉, 前野将太, 黒田大介, 福井暁彦, 成田憲保, はしもと じょーじ, 櫻井友里, 中村小百合, 高橋隼, 谷川智康, 伊藤孝士, 吉田二美, BURHONOV Otabek, 渡邉誠, 今井正尭, 倉本圭, 関口朋彦, 石黒正晃, 日本惑星科学会秋季講演会予稿集(Web), 2016, 2016

JUICE/GALA-J (2): Science objectives of the GAnymede Laser Altimeter (GALA) onboard JUICE space-craft
木村淳, 鎌田俊一, 松本晃治, 松本晃治, 押上祥子, 並木則行, 並木則行, 倉本圭, 佐々木晶, 塩谷圭吾, 塩谷圭吾, 小林正規, 小林進悟, 荒木博志, 荒木博志, 野田寛大, 野田寛大, 石橋高, 齋藤義文, HUSSMANN Hauke, 日本惑星科学会秋季講演会予稿集(Web), 2016, 2016

Book review
Kuramoto K., Planetary People - The Japanese Society for Planetary Sciences, 25, 1, 28, 28, 2016
The Japanese Society for Planetary Sciences, Japanese

集積期における火星マントルへの水の分配
齊藤大晶, 倉本圭, 日本地球惑星科学連合大会予稿集(Web), 2016, ROMBUNNO.PPS11‐13 (WEB ONLY), 2016
Japanese

湿潤大気に現れる対流圏界面高度の異なる二つの大気構造
大西将徳, はしもと じょーじ, 倉本圭, 高橋芳幸, 石渡正樹, 高橋康人, 林祥介, 日本地球惑星科学連合大会予稿集(Web), 2016, ROMBUNNO.PPS11‐17 (WEB ONLY), 2016
Japanese

太陽系生命前駆環境の実証的解明のための統合研究プログラム
倉本圭, 日本地球惑星科学連合大会予稿集(Web), 2016, ROMBUNNO.U06‐13 (WEB ONLY), 2016
Japanese

A massive primordial‐atmosphere on proto‐Titan formed in a gas‐starved disk
MIKAMI Takashi, TAKAHASHI Yasuto, KURAMOTO Kiyoshi, KURAMOTO Kiyoshi, 日本地球惑星科学連合大会予稿集(Web), 2016, ROMBUNNO.PPS01‐03 (WEB ONLY), 2016
English

JUICE/GALA‐J (2): Science objectives of the GAnymede Laser Altimeter (GALA) for the JUICE mission
KIMURA Jun, KAMATA Shunichi, MATSUMOTO Koji, OSHIGAMI Shoko, NAMIKI Noriyuki, KURAMOTO Kiyoshi, SASAKI Sho, ENYA Keigo, KOBAYASHI Masanori, KOBAYASHI Shingo, ARAKI Hiroshi, NODA Hirotomo, ISHIBASHI Ko, SAITO Yoshifumi, HUSSMANN Hauke, LINGENAUBER Kay, 日本地球惑星科学連合大会予稿集(Web), 2016, 2, ROMBUNNO.PPS11‐P05 (WEB ONLY), 243, 2016
Japan Society for Aeronautical and Space Sciences, English

JUICE/GALA‐J (1): The Ganymede Laser Altimeter (GALA) for the JUICE mission―Introduction, current status, and role of the Japan team
ENYA Keigo, NAMIKI Noriyuki, KOBAYASHI Masanori, KIMURA Jun, ARAKI Hiroshi, NODA Hirotomo, OSHIGAMI Shoko, KASHIMA Shingo, ISHIBASHI Ko, KOBAYASHI Shingo, OZAKI Masanobu, MIZUNO Takahide, UTSUNOMIYA Shin, SAITO Yoshifumi, TOUHARA Kazuyuki, KAMATA Shunichi, MATSUMOTO Koji, KURAMOTO Kiyoshi, SASAKI Sho, IWAMURA Satoru, IIDA Teruhito, MATSUMOTO Yoshiaki, FUJII Masanori, FUJISHIRO Naofumi, YAMAMURO Tomoyasu, LINGENAUBER Kay, BEHNKE Thomas, OBERST Juergen, JAENCHEN Judit, LOETZKE Horst‐Georg, MICHAELIS Harald, HUSSMANN Hauke, 日本地球惑星科学連合大会予稿集(Web), 2016, ROMBUNNO.PPS11‐26 (WEB ONLY), 2016
English

Investigation of Ganymede's interior structure through tidal deformation measurements by JUICE/GALA
Kamata Shunichi, Kimura Jun, Matsumoto Koji, Kuramoto Kiyoshi, 第48回月・惑星シンポジウム = Proceedings of the 48th ISAS Lunar and Planetary Symposium, Jul. 2015
48th ISAS Lunar and Planetary Symposium (July 29-31, 2015. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS), Japanese

Mars satellite sample return mission and its sciences
Kuramoto Kiyoshi, Mars satellite sample return mission science team, 地球電磁気・地球惑星圏学会総会及び講演会予稿集(CD-ROM), 138th, ROMBUNNO.R009‐24, Jul. 2015
48th ISAS Lunar and Planetary Symposium (July 29-31, 2015. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS), English

木星型惑星を想定した雲対流の数値計算
杉山耕一朗, 小高正嗣, 中島健介, 倉本圭, 林祥介, 日本気象学会大会講演予稿集, 107, 315, 30 Apr. 2015
Japanese

水蒸気大気の圏界面の推定とハビタブルゾーンの内側境界
大西将徳, はしもと じょーじ, 倉本圭, 高橋芳幸, 石渡正樹, 高橋康人, 林祥介, 日本気象学会大会講演予稿集, 107, 323, 30 Apr. 2015
Japanese

比較惑星学
倉本圭, パリティ, 30, 4, 21-22,1, 01 Apr. 2015
Japanese

比較惑星学 (30周年企画 特集 物理科学,この30年(1)) -- (地球惑星物理)
倉本 圭, パリティ, 30, 4, 21, 22,1, Apr. 2015
丸善, Japanese

周惑星ガス円盤内で形成する巨大氷衛星が獲得する原始大気
三上峻, 高橋康人, 倉本圭, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2015, 2015

原始太陽系星雲散逸期の火星形成:熱史と大気-内部間揮発性物質分配
齊藤大晶, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2015, 2015

JUICEレーザ高度計(GALA)による潮汐変形計測から探るガニメデの内部構造
鎌田俊一, 木村淳, 松本晃治, 並木則行, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2015, 2015

放射対流平衡モデルによる水蒸気大気の圏界面温度の推定
大西将徳, はしもと じょーじ, 倉本圭, 高橋芳幸, 石渡正樹, 高橋康人, 林祥介, 日本惑星科学会秋季講演会予稿集(Web), 2015, 2015

木星大気放射冷却に対する雲対流の寄与
高橋康人, はしもと じょーじ, 石渡正樹, 高橋芳幸, 杉山耕一朗, 大西将徳, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2015, 2015

Science targets of the GAnymede Laser Altimeter (GALA) aboard Jupiter Icy Moons Explorer (JUICE)
木村淳, 並木則行, 鎌田俊一, 松本晃治, 押上祥子, 塩谷圭吾, 倉本圭, 日本惑星科学会秋季講演会予稿集(Web), 2015, 2015

D309 木星型惑星を想定した雲対流の数値計算(大気力学,一般口頭発表)
杉山 耕一朗, 小高 正嗣, 中島 健介, 倉本 圭, 林 祥介, 大会講演予講集, 107, 315, 315, 2015
日本気象学会, Japanese

P305 水蒸気大気の圏界面の推定とハビタブルゾーンの内側境界(ポスター・セッション)
大西 将徳, はしもと じょーじ, 倉本 圭, 高橋 芳幸, 石渡 正樹, 高橋 康人, 林 祥介, 大会講演予講集, 107, 323, 323, 2015
日本気象学会, Japanese

Report of Workshop on Mars Science
Takahashi Y. O., Kuramoto K., Planetary People - The Japanese Society for Planetary Sciences, 24, 1, 75, 77, 2015
The Japanese Society for Planetary Sciences, Japanese

Preface
Kuramoto K., Planetary People - The Japanese Society for Planetary Sciences, 24, 1, 3, 3, 2015
The Japanese Society for Planetary Sciences, Japanese

Report of Workshop on Satellite Systems 2015
Tanigawa T., Kimura J., Sekine Y., Kuramoto K., Ohtsuki K., Tanaka H., Okuzumi S., Planetary People - The Japanese Society for Planetary Sciences, 24, 4, 343, 345, 2015
The Japanese Society for Planetary Sciences, Japanese

火星衛星サンプルリターン機による火星大気観測の可能性
今村剛, 小郷原一智, 田口真, 山本真行, 笠羽康正, 青木翔平, 坂野井健, 黒田剛史, 笠井康子, 高橋芳幸, 野口克行, 倉本圭, 地球電磁気・地球惑星圏学会総会及び講演会予稿集(CD-ROM), 138th, ROMBUNNO.R009‐26, 2015
Japanese

火星衛星サンプルリターン計画:火星衛星から探る火星圏の科学目的
寺田直樹, 関華奈子, 二穴喜文, LEBLANC Francois, 松岡彩子, 横田勝一郎, 齋藤義文, 山崎敦, 亀田真吾, 長勇一郎, 倉本圭, 地球電磁気・地球惑星圏学会総会及び講演会予稿集(CD-ROM), 138th, ROMBUNNO.R009‐25, 2015
Japanese

「惑星科学/太陽系科学研究領域の目標・戦略・工程表」の概要
倉本圭, 荒井朋子, 小林直樹, 杉田精司, 橘省吾, 寺田直樹, 並木則行, 松本晃治, 渡邊誠一郎, 日本地球惑星科学連合大会予稿集(Web), 2015, ROMBUNNO.PPS21‐38 (WEB ONLY), 2015
Japanese

GJ1214b大気の流体力学的散逸
渡辺健介, 倉本圭, 日本地球惑星科学連合大会予稿集(Web), 2015, ROMBUNNO.PPS21‐22 (WEB ONLY), 2015
Japanese

生命保有可能系外惑星GJ667Ccの気候モデリング
成田一輝, 倉本圭, 日本地球惑星科学連合大会予稿集(Web), 2015, ROMBUNNO.PPS21‐23 (WEB ONLY), 2015
Japanese

木星型惑星を想定した雲対流の数値計算
杉山耕一朗, 中島健介, 小高正嗣, 倉本圭, 林祥介, 日本地球惑星科学連合大会予稿集(Web), 2015, ROMBUNNO.PPS01‐01 (WEB ONLY), 2015
Japanese

原始太陽系星雲中で成長する火星の混成型原始大気の熱的構造
齊藤大晶, 倉本圭, 日本地球惑星科学連合大会予稿集(Web), 2015, ROMBUNNO.PPS21‐16 (WEB ONLY), 2015
Japanese

形成期の水星におけるコア‐マントル間の硫黄の分配と水星の材料物質
笹森映里, 倉本圭, 日本地球惑星科学連合大会予稿集(Web), 2015, ROMBUNNO.PPS21‐05 (WEB ONLY), 2015
Japanese

水蒸気大気の圏界面の推定とハビタブルゾーンの内側境界
大西将徳, はしもと じょーじ, 倉本圭, 高橋芳幸, 石渡正樹, 高橋康人, 林祥介, 日本地球惑星科学連合大会予稿集(Web), 2015, ROMBUNNO.PPS21‐27 (WEB ONLY), 2015
Japanese

Interior evolution of Ganymede and its surface manifestation: toward JUICE measurements
KIMURA Jun, KURAMOTO Kiyoshi, 日本地球惑星科学連合大会予稿集(Web), 2015, ROMBUNNO.PPS01‐11 (WEB ONLY), 2015
English

The radiative cooling and the solar heating in Jovian troposphere
TAKAHASHI Yasuto, HASHIMOTO George, ISHIWATARI Masaki, TAKAHASHI Yoshiyuki O, SUGIYAMA Ko‐ichiro, ONISHI Masanori, KURAMOTO Kiyoshi, 日本地球惑星科学連合大会予稿集(Web), 2015, ROMBUNNO.PPS01‐02 (WEB ONLY), 2015
English

Tidal deformation of Ganymede and effects of a subsurface ocean: a model calculation in preparation for JUICE
KAMATA Shunichi, KIMURA Jun, MATSUMOTO Koji, NIMMO Francis, KURAMOTO Kiyoshi, 日本地球惑星科学連合大会予稿集(Web), 2015, ROMBUNNO.PPS01‐10 (WEB ONLY), 2015
English

同期回転惑星の大気循環における雲の効果に関する数値実験
石渡正樹, 阿部豊, 倉本圭, 高橋芳幸, 中島健介, 林祥介, 日本気象学会大会講演予稿集, 106, 144, 30 Sep. 2014
Japanese

木星大気の雲対流と大気構造
杉山耕一朗, 中島健介, 小高正嗣, 倉本圭, 林祥介, 日本気象学会大会講演予稿集, 106, 140, 30 Sep. 2014
Japanese

系外惑星大気の3次元計算のための放射モデル開発
大西将徳, はしもと じょーじ, 倉本圭, 高橋芳幸, 石渡正樹, 高橋康人, 林祥介, 日本気象学会大会講演予稿集, 106, 145, 30 Sep. 2014
Japanese

O1-05 同期回転惑星大気の数値実験 : 昼夜間熱輸送に関する検討(口頭発表セッション1 惑星大気,口頭発表)
石渡 正樹, 阿部 豊, 倉本 圭, 高橋 芳幸, 中島 健介, 林 祥介, 日本惑星科学会秋期講演会予稿集, 2014, "O1, 05", 10 Sep. 2014
日本惑星科学会, Japanese

P1-01 木星型惑星を想定した雲対流の数値計算(ポスターセッション1,ポスター発表)
杉山 耕一朗, 中島 健介, 小高 正嗣, 倉本 圭, 林 祥介, 日本惑星科学会秋期講演会予稿集, 2014, "P1, 01", 10 Sep. 2014
日本惑星科学会, Japanese

O3-01 原始太陽系星雲ガス中で集積成長する火星の混成型原始大気とその保温効果(口頭発表セッション3 惑星形成I,口頭発表)
齊藤 大晶, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2014, "O3, 01", 10 Sep. 2014
日本惑星科学会, Japanese

O3-04 周惑星ガス円盤中で形成する巨大氷衛星の原始大気(口頭発表セッション3 惑星形成I,口頭発表)
三上 峻, 高橋 康人, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2014, "O3, 04", 10 Sep. 2014
日本惑星科学会, Japanese

O9-06 形成期の水星におけるコア-マントル間の硫黄の分配(口頭発表セッション9 月・内部構造,口頭発表)
笹森 映里, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2014, "O9, 06", 10 Sep. 2014
日本惑星科学会, Japanese

O1-04 大気大循環モデルのための放射モデル開発 : 同期回転惑星大気(口頭発表セッション1 惑星大気,口頭発表)
大西 将徳, はしもと じょーじ, 倉本 圭, 高橋 芳幸, 日本惑星科学会秋期講演会予稿集, 2014, "O1, 04", 10 Sep. 2014
日本惑星科学会, Japanese

O2-05 巨大ガス惑星の雲層構造と放射冷却過程(口頭発表セッション2 系外惑星,口頭発表)
高橋 康人, はしもと じょーじ, 石渡 正樹, 高橋 芳幸, 大西 将徳, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2014, "O2, 05", 10 Sep. 2014
日本惑星科学会, Japanese

ガリレオ衛星食を用いた木星大気探査:系外惑星大気のトランジット観測への応用可能性
津村耕司, 白籏麻衣, 有松亘, 高橋康人, 倉本圭, 松浦周二, 和田武彦, 美濃和陽典, 早野裕, 中島健介, 中本泰史, 木村淳, 本田親寿, 江上英一, SURACE Jason, 日本天文学会年会講演予稿集, 2014, 170, 20 Aug. 2014
Japanese

A proposal for determining the lunar crustal thickness by one penetrator probe using impact seismic events
Kobayashi Naoki, Ishihara Yoshiaki, Yamada Ryuhei, Murakami Hideki, Shiraishi Hiroaki, Tanaka Satoshi, Hayakawa Masahiko, Arakawa Masahiko, Morota Tomokatsu, Kawamura Taichi, Kuramoto Kiyoshi, Gotoh Ken, Yamamoto Tetsuo, The Lunar Internal Structure WG, 第47回月・惑星シンポジウム = Proceedings of the 47th ISAS Lunar and Planetary Symposium, Aug. 2014
47th ISAS Lunar and Planetary Symposium (August 4-6, 2014. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency(JAXA)(ISAS), Japanese

巨大惑星を想定した雲対流の2次元数値計算
杉山耕一朗, 小高正嗣, 中島健介, 倉本圭, 林祥介, 日本気象学会大会講演予稿集, 105, 403, 30 Apr. 2014
Japanese

Exploration of Enceladus&apos; Water-Rich Plumes toward Understanding of Chemistry and Biology of the Interior Ocean
Sekine, Yasuhito, Takano, Yoshinori, Yano, Hajime, Funase, Ryu, Takai, Ken, Ishihara, Morio, Shibuya, Takazo, Tachibana, Shogo, Kuramoto, Kiyoshi, Yabuta, Hikaru, Kimura, Jun, Furukawa, Yoshihiro, TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN, 12, ists29, 229, 238, 2014
エンセラダスの南極付近から噴出するプリュームの発見は,氷衛星の内部海の海水や海中の揮発性成分や固体成分の直接サンプリングの可能性を示した大きなブレイクスルーであるといえる.これまでカッシーニ探査によって,プリューム物質は岩石成分と相互作用する液体の内部海に由来していることが明らかになったが,サンプリング時の相対速度が大きいこと,質量分析装置の分解能が低いことなどの問題があり,内部海の化学組成や温度条件,海の存続時間など,生命存在の可能性を制約できる情報は乏しい.本論文では,エンセラダス・プリューム物質の高精度その場質量分析とサンプルリターンによる詳細な物質分析を行うことで,内部海の化学組成の解明,初期太陽系物質進化の制約,そして生命存在可能性を探ることを目的とする探査計画を提案する.本提案は,"宇宙に生命は存在するのか"という根源的な問いに対して,理・工学の様々な分野での次世代を担う若手研究者が惑星探査に参入し結集する点が画期的であり,我が国の科学・技術界全体に対しても極めて大きな波及効果をもつ., 日本惑星科学会, Japanese

P446 巨大惑星を想定した雲対流の2次元数値計算(ポスターセッション)
杉山 耕一朗, 小高 正嗣, 中島 健介, 倉本 圭, 林 祥介, 大会講演予講集, 105, 403, 403, 2014
日本気象学会, Japanese

B163 木星大気の雲対流と大気構造(惑星大気科学の現在,スペシャル・セッション)
杉山 耕一朗, 中島 健介, 小高 正嗣, 倉本 圭, 林 祥介, 大会講演予講集, 106, 140, 140, 2014
日本気象学会, Japanese

B167 同期回転惑星の大気循環における雲の効果に関する数値実験(惑星大気科学の現在,スペシャル・セッション)
石渡 正樹, 阿部 豊, 倉本 圭, 高橋 芳幸, 中島 健介, 林 祥介, 大会講演予講集, 106, 144, 144, 2014
日本気象学会, Japanese

B168 系外惑星大気の3次元計算のための放射モデル開発(惑星大気科学の現在,スペシャル・セッション)
大西 将徳, はしもと じょーじ, 倉本 圭, 高橋 芳幸, 石渡 正樹, 高橋 康人, 林 祥介, 大会講演予講集, 106, 145, 145, 2014
日本気象学会, Japanese

A round table talk on solar system exploration with Mizutani-san
Mizutani H., Yamamoto T., Hayashi Y., Kuramoto K., Kokubo E., Hashimoto G.L., Planetary People - The Japanese Society for Planetary Sciences, 23, 2, 120, 129, 2014
2013年9月17日から20日まで,北海道ニセコ町で惑星科学フロンティアセミナー2013(主催・惑星科学フロンティアセミナー実行委員会)が開催されました.この中で,講師に迎えた独立行政法人宇宙航空研究開発機構(JAXA)の宇宙科学研究所(ISAS)名誉教授で科学雑誌Newton編集長の水谷仁氏を囲んで,ISAS在任中の思い出を語り合う座談会が企画されました.月探査機LUNAR-A計画の狙いに始まり,宇宙科学研究をどのように展開すればよいのか研究手法にも話題が及び,さらには惑星科学コミュニティーが中心となって次なる惑星科学の研究テーマをどう見出すべきなのかといった内容が話し合われました.以下,座談会で行われた主なやり取りを紹介します.(敬称略), The Japanese Society for Planetary Sciences, Japanese

Report of Workshop on Satellite Systems
Tanigawa T., Okuzumi S., Kimura J., Kuramoto K., Ohtsuki K., Planetary People - The Japanese Society for Planetary Sciences, 23, 4, 386, 388, 2014
The Japanese Society for Planetary Sciences, Japanese

Report on the lunar science seminar
Ohtake M., Kuramoto K., Murakami H., Fujimoto M., Hashimoto T., Yamamoto T., Planetary People - The Japanese Society for Planetary Sciences, 23, 4, 396, 397, 2014
The Japanese Society for Planetary Sciences, Japanese

系外惑星気候の多様性の探索:雲の存在を考慮した同期回転惑星大気の数値実験
石渡正樹, 阿部豊, 倉本圭, 高橋芳幸, 細氷(Web), 60, 30-31 (WEB ONLY), 2014
Japanese

Numerical simulations of Jupiter’s moist convection layer: Structure and dynamics in statistically steady states
SUGIYAMA Ko‐ichiro, NAKAJIMA Kensuke, ODAKA Masatsugu, KURAMOTO Kiyoshi, HAYASHI Yoshi‐Yuki, Extended Abstracts. 6th International Workshop on Global Cloud Resolving Modeling. 3rd International Workshop on Nonhydrostatic Numerical Models. RIKEN Symposium, 2014, 33, 34, 2014
English

Exploration of Enceladus&apos; Water-Rich Plumes toward Understanding of Chemistry and Biology of the Interior Ocean
Sekine, Yasuhito, Takano, Yoshinori, Yano, Hajime, Funase, Ryu, Takai, Ken, Ishihara, Morio, Shibuya, Takazo, Tachibana, Shogo, Kuramoto, Kiyoshi, Yabuta, Hikaru, Kimura, Jun, Furukawa, Yoshihiro, TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN, 12, ists29, TK.7-TK.11 (J-STAGE), 2014
English

P3-17 Current status of the Lunar Landing Mission : SELENE-2(4)
Tanaka Satoshi, Mitani Takefumi, Otake Hisashi, Kobayashi Naoki, Ogawa Kazunori, Hashimoto Tatsuaki, Hoshino Takeshi, Otsuki Masatsugu, Kimura Jun, Kuramoto Kiyoshi, Wakabayashi Sachiko, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 2013, "P3, 17", 20 Nov. 2013
The Japanese Society for Planetary Sciences, Japanese

O3-10 HD 209458b大気の流体力学的散逸の数値モデリング(口頭発表セッション3(系外惑星),口頭発表)
渡辺 健介, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2013, "O3, 10", 20 Nov. 2013
日本惑星科学会, Japanese

O6-05 周惑星ガス円盤中で集積する巨大氷衛星の原始大気(口頭発表セッション6(衛星系・リング),口頭発表)
三上 峻, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2013, "O6, 05", 20 Nov. 2013
日本惑星科学会, Japanese

O6-07 木星の影におけるガニメデからの近赤外線放射(口頭発表セッション6(衛星系・リング),口頭発表)
津村 耕司, 新井 俊明, 有松 亘, 江上 英一, 本田 親寿, 木村 淳, 倉本 圭, 松浦 周二, 中島 健介, 中本 泰史, 白籏 麻衣, Surace Jason, 和田 武彦, 日本惑星科学会秋期講演会予稿集, 2013, "O6, 07", 20 Nov. 2013
日本惑星科学会, Japanese

O6-08 Science targets of the Ganymede laser altimeter (GALA) aboard Jupiter Icy Moons Explorer(JUICE)
Hussmann Hauke, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 2013, "O6, 08", 20 Nov. 2013
A new mission to Jupiter system, JUICE, has started by European Space Agency. The GALA, which will be developed by international collaboration of scientists and engineers in Germany, Switzerland, and Japan, has been selected by ESA for JUICE mission payload and measures distance between the spacecraft and the surface of the satellite from time of flight of a laser pulse. GALA will focus on geodetic and geophysical investigations of the icy satellites Europa, Ganymede and Callisto. Here, we describe the scientific objectives., The Japanese Society for Planetary Sciences, Japanese

O13-02 木星大気における雲の凝結メカニズム : 放射対流平衡モデルを用いた大気成分鉛直分布の推定(口頭発表セッション13(惑星大気),口頭発表)
高橋 康人, はしもと じょーじ, 大西 将徳, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2013, "O13, 02", 20 Nov. 2013
日本惑星科学会, Japanese

O13-03 同期回転惑星大気の数値実験 : 非灰色放射スキームと雲スキームを用いた場合(口頭発表セッション13(惑星大気),口頭発表)
石渡 正樹, 阿部 豊, 倉本 圭, 高橋 芳幸, 日本惑星科学会秋期講演会予稿集, 2013, "O13, 03", 20 Nov. 2013
日本惑星科学会, Japanese

P2-20 Formation of a metallic core and extensional tectonics of Ganymede with implication for divergent evolutionary paths of Callisto and Titan
木村 淳, 倉本 圭, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 2013, "P2, 20", 20 Nov. 2013
Jupiter's largest moon Ganymede has an abundant evidence of extensional tectonics resulting from global expansion in relatively young age, and has a large metallic core which is implied by the existence of the intrinsic magnetic field and small value of the moment of inertia factor. To investigate these origins, here we show dehydration models of primordial hydrous silicate and metal-mixed core, which is heated by long-lived radiogenic isotopes and becomes dehydrated. The volume expansion accompanying the dehydration is possibly enough large for the extensional tectonics and its timing is consistent with the cratering age. Dehydration also results in the sharp viscosity increase, and the central temperature possibly exceeds the eutectic point of conductive materials, allowing the formation of a metallic core. Actual Ganymede's interior (and possibly also Titan) can form a conductive core while slightly smaller Callisto can escape from sufficient heating. This may explain the observed difference in the surface geology and internal structure among the giant icy moons., The Japanese Society for Planetary Sciences, Japanese

雲の存在を考慮した同期回転惑星大気の数値実験
石渡正樹, 阿部豊, 倉本圭, 高橋芳幸, 日本気象学会大会講演予稿集, 104, 95, 31 Oct. 2013
Japanese

木星大気の雲対流の直接数値計算:雲対流の間欠性に関する考察
杉山耕一朗, 小高正嗣, 中島健介, 石渡正樹, 倉本圭, 高橋芳幸, 西澤誠也, 林祥介, 日本気象学会大会講演予稿集, 103, 376, 30 Apr. 2013
Japanese

惑星科学研究センター(CPS)における知見アーカイブ
杉山耕一朗, 鈴木絢子, 中村友昭, 真鍋翔, 谷伊織, 辰巳信平, 加藤則行, 松本恵, 山千代真規, 村上久, 鶴巻亮一, 竹腰達哉, 押川智美, 三上峻, 倉本圭, 林祥介, 日本気象学会大会講演予稿集, 103, 377, 30 Apr. 2013
Japanese

D411 木星大気の雲対流の直接数値計算:雲対流の間欠性に関する考察(大気力学,口頭発表)
杉山 耕一朗, 小高 正嗣, 中島 健介, 石渡 正樹, 倉本 圭, 高橋 芳幸, 西澤 誠也, 林 祥介, 大会講演予講集, 103, 376, 376, 2013
日本気象学会, Japanese

A report on the 2nd seminar for the forefront of planetary science
Kimura J., Kurita K., Kuri M., Kuramoto K., Hashimoto G., Planetary People - The Japanese Society for Planetary Sciences, 22, 1, 44, 47, 2013
The Japanese Society for Planetary Sciences, Japanese

Report of Workshop on Satellite Systems
Tanigawa T., Okuzumi S., Kimura J., Kuramoto K., Ohtsuki K., Planetary People - The Japanese Society for Planetary Sciences, 22, 4, 274, 276, 2013
The Japanese Society for Planetary Sciences, Japanese

木星の影におけるガニメデからの近赤外線放射
津村耕司, 新井俊明, 有松亘, 江上英一, 本田親寿, 木村淳, 倉本圭, 松浦周二, 中島健介, 中本泰史, 白籏麻衣, SURACE Jason, 和田武彦, 日本惑星科学会秋季講演会予稿集, 2013, 53, 2013
Japanese

次期月探査計画SELENE‐2の検討状況(4)
田中智, 三谷烈史, 大嶽久志, 小林直樹, 小川和律, 橋本樹明, 星野健, 大槻真嗣, 木村淳, 倉本圭, 若林幸子, 日本惑星科学会秋季講演会予稿集, 2013, 178, 2013
Japanese

JUICE搭載レーザ高度計(GALA)のサイエンス目標
木村淳, HUSSMANN Hauke, 並木則行, 鎌田俊一, 松本晃治, 倉本圭, 佐々木晶, 平田成, 日本惑星科学会秋季講演会予稿集, 2013, 54, 2013
Japanese

木星大気における雲の凝結メカニズム:放射対流平衡モデルを用いた大気成分鉛直分布の推定
高橋康人, はしもと じょーじ, 大西将徳, 倉本圭, 日本惑星科学会秋季講演会予稿集, 2013, 109, 2013
Japanese

ガニメデの金属核形成と膨張地形形成:カリスト・タイタンとの進化の分岐
木村淳, 倉本圭, 日本惑星科学会秋季講演会予稿集, 2013, 156, 2013
Japanese

同期回転惑星大気の数値実験:非灰色放射スキームと雲スキームを用いた場合
石渡正樹, 阿部豊, 倉本圭, 高橋芳幸, 日本惑星科学会秋季講演会予稿集, 2013, 110, 2013
Japanese

HD209458b大気の流体力学的散逸の数値モデリング
渡辺健介, 倉本圭, 日本惑星科学会秋季講演会予稿集, 2013, 26, 2013
Japanese

周惑星ガス円盤中で集積する巨大氷衛星の原始大気
三上峻, 倉本圭, 日本惑星科学会秋季講演会予稿集, 2013, 51, 2013
Japanese

D412 惑星科学研究センター(CPS)における知見アーカイブ(大気力学,口頭発表)
杉山 耕一朗, 鈴木 絢子, 中村 友昭, 真鍋 翔, 谷 伊織, 辰巳 信平, 加藤 則行, 松本 恵, 山千代 真規, 村上 久, 鶴巻 亮一, 竹腰 達哉, 押川 智美, 三上 峻, 倉本 圭, 林 祥介, 惑星科学研究センター, 大会講演予講集, 103, 377, 377, 2013
日本気象学会, Japanese

D102 雲の存在を考慮した同期回転惑星大気の数値実験(大気力学,口頭発表)
石渡 正樹, 阿部 豊, 倉本 圭, 高橋 芳幸, 大会講演予講集, 104, 95, 95, 2013
日本気象学会, Japanese

P1-07 Current status of the Lunar Landing Mission : SELENE-2(3)
Tanaka Satoshi, Mitani Takefumi, Otake Hisashi, Ogawa Kazunori, Kobayashi Naoki, Iijima Yuichi, Hashimoto Tatsuaki, Hoshino Takeshi, Otsuki Masatsugu, Kimura Jun, Kuramoto Kiyoshi, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 2012, 102, 102, 24 Oct. 2012
The Japanese Society for Planetary Sciences, Japanese

O4-05 木星の対流圏界面高度はどのように決まっているのか : 放射対流平衡モデルを用いた解析(口頭発表セッション4(惑星大気,衝突科学I),口頭発表)
高橋 康人, 倉本 圭, はしもと じょ一じ, 大西 将徳, 日本惑星科学会秋期講演会予稿集, 2012, 41, 41, 24 Oct. 2012
日本惑星科学会, Japanese

「将来木星圏・土星圏探査計画へのサイエンス:その2」木星の大気構造と雲対流
杉山耕一朗, 中島健介, 小高正嗣, 石渡正樹, 倉本圭, 高橋芳幸, 林祥介, 日本惑星科学会誌 遊・星・人, 21, 1, 39, 44, 25 Mar. 2012
Japanese

Report of the Mini Workshop on the Formation of Satellite Systems
Tanigawa T., Okuzumi S., Kuramoto K., Ohtsuki K., Planetary People - The Japanese Society for Planetary Sciences, 21, 4, 377, 379, 2012
The Japanese Society for Planetary Sciences, Japanese

Chronological table of lunar geologic history
Morota T., Kuramoto K., Takahashi F., Planetary People - The Japanese Society for Planetary Sciences, 21, 1, 57, 63, 2012
現在,月着陸計画SELENE-2の検討が進められている.更にその先に目指すサンプルリターン計画やネットワーク観測による内部構造探査,有人月探査計画も含めて,各々のミッションを着実に実現し,得られる理学成果から月の理解を積み上げ式に発展させるためには,一連の月探査計画の骨組みとなる理学目標の設定が必須であることは言うまでもない.一方で近年の月探査データの解析研究,月試料の分析研究から新たな観測事実が得られるにつれ,月の理解はますます複雑化してきたように思われる.そのため専門家の間でも月科学の全体描像の整理と将来月探査で狙うべき科学対象の整理が十分にできていないのが現状である.そこで我々は月科学における理解の現状の整理を目的として,月の歴史図の作成を進めている.本稿ではその最新版を紹介するとともに,月の起源・進化解明に向けて月科学の目指すべき方向性について議論したい., The Japanese Society for Planetary Sciences, Japanese

Atmospheric structure and cloud convection in Jupiter's atmosphere (Special issue: Sciences toward future explorations for the Jovian and Saturnian systems)
Sugiyama K., Nakajima K., Odaka M., Ishiwatari M., Kuramoto K., Takahashi Y. O., Hayashi Y.-Y., Planetary People - The Japanese Society for Planetary Sciences, 21, 1, 39, 44, 2012
光の透過性の問題で,木星雲層の大気構造の観測は断片的・間接的にならざるを得ず,その構造は未だよくわかっていない.1970年代に,鉛直1次元の平衡雲凝結モデルによって大気構造が理論的に調べられ,組成の異なる3成分の雲が別々の高度に分かれて存在するという描像が作られた.この描像は,一般的に受け入れられているが,大気の運動や降水等の雲微物理過程によって変化するはずである.筆者らはH_2OとNH_3の凝結とNH_4SHの生成反応を考慮した雲解像モデルを開発し,多数の雲の生成消滅が繰り返された結果として決まる大気構造を調べてきた.本稿ではこれまでの木星雲層の大気構造の認識を概観しつつ,筆者らの最近の研究結果を紹介する., The Japanese Society for Planetary Sciences, Japanese

S21-04 木星型惑星を想定したH_2-He大気の鉛直一次元放射対流平衡モデル : 大気冷却率と熱構造の下部境界条件依存性(口頭セッション21:惑星観測,口頭発表)
高橋 康人, 倉本 圭, 石渡 正樹, 日本惑星科学会秋期講演会予稿集, 2011, 39, 39, 23 Oct. 2011
日本惑星科学会, Japanese

S22-07P Current status of the Lunar Landing Mission : SELENE-2(2)
Tanaka Satoshi, Mitani Takefumi, Otake Hisashi, Ogawa Kazunori, Kobayashi Naoki, Iijima Yuichi, Hashimoto Tatsuaki, Hoshino Takeshi, Otsuki Masatsugu, Kimura Jun, Kuramoto Kiyoshi, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 2011, 127, 127, 23 Oct. 2011
The Japanese Society for Planetary Sciences, Japanese

S32-07 Lax-Friedrichs法による流体力学的大気散逸の数値計算(口頭セッション32:惑星環境進化,口頭発表)
梅本 隆史, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2011, 77, 77, 23 Oct. 2011
日本惑星科学会, Japanese

S32-09 薄い周惑星円盤で集積する巨大氷衛星の原始大気の放射特性とその保温効果(口頭セッション32:惑星環境進化,口頭発表)
岡田 英誉, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2011, 79, 79, 23 Oct. 2011
日本惑星科学会, Japanese

Strategic study of lunar and planetary explorations in coming decade : Panel report on top sciences
Ohtani E., Kimura J., Takahashi Y., Nakajima K., Nakamoto T., Miyoshi Y., Kobayashi K., Yamagishi A., Namiki N., Kobayashi N., Demura H., Kuramoto K., Ohtsuki K., Imamura T., Terada N., Watanabe S., Arakawa M., Ito T., Yurimoto H., Watanabe J., Planetary People - The Japanese Society for Planetary Sciences, 20, 4, 349, 365, 2011
「月惑星探査の来たる10年」検討では第一段階で5つのパネルの各分野に於ける第一級の科学について議論した.そのとりまとめを報告する.地球型惑星固体探査パネルでは,月惑星内部構造の解明,年代学・物質科学の展開による月惑星進化の解明,固体部分と結合した表層環境の変動性の解明,が挙げられた.地球型惑星大気・磁気圏探査パネルは複数学会に跨がる学際性を考慮して,提案内容に学会間で齟齬が生じないように現在も摺り合わせを進めている.本稿では主たる対象天体を火星にしぼって第一級の科学を論じる.小天体パネルでは始原的・より未分化な天体への段階的な探査と,発見段階から理解段階へ進むための同一小天体の再探査が提案された.木星型惑星・氷衛星・系外惑星パネルは広範な科学テーマの中から,木星の大気と磁気圏探査,氷衛星でのハビタブル環境の探査,系外惑星でも生命存在可能環境と生命兆候の発見について具体的な議論を行った.アストロバイオロジーパネルでは現実的な近未来の目標として火星生命探査を,長期的な目標として氷衛星・小天体生命探査を目指した観測装置開発が検討された.これらのまとめを元に「月惑星探査の来たる10年」検討は2011年7月より第二段階に移行し,ミッション提案・観測機器提案の応募を受け付けた., The Japanese Society for Planetary Sciences, Japanese

315 原始惑星系円盤初期における物質の降着年代分布(オーラルセッション8 ガス惑星・リング・原始惑星系円盤)
安達 俊貴, 福井 隆, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2010, 66, 66, 06 Oct. 2010
日本惑星科学会, Japanese

P017 Current status of the Lunar Landing Mission : SELENE-2
Tanaka Satoshi, Iijima Yuichi, Mitani Takefumi, Otake Hisashi, Ogawa Kazunori, Kobayashi Naoki, Hashimoto Tatsuaki, Hoshino Takeshi, Otsuki Masatsugu, Kimura Jun, Kuramoto Kiyoshi, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 2010, 97, 97, 06 Oct. 2010
The Japanese Society for Planetary Sciences, Japanese

P030 Dehydration of hydrous rock contributing to the internal differentiation of giant icy satellites
木村 淳, 倉本 圭, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 2010, 110, 110, 06 Oct. 2010
The Japanese Society for Planetary Sciences, Japanese

地球の奇跡はどれほどの奇跡か? ([Newton]創刊350号記念大特集 地球--地球を「特別な存在」にしたものは何か? 今こそ知っておきたい母なる惑星の「事実」) -- (なぜ,生命をはぐくむ惑星となったのか? 惑星「地球」の奇跡)
倉本 圭, ニュートン, 30, 9, 64, 67, Sep. 2010
ニュートンプレス, Japanese

Weak-field dynamo emerging in a rotating spherical shell with stress-free top and no-slip bottom boundaries
SASAKI Youhei, Takehiro Shin-ichi, Hayashi Yoshi-Yuki, Kuramoto Kiyoshi, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2010, 211, 211, 2010
Numerical experiments of MHD dynamo in a rotating spherical shell with stress-free top and no-slip bottom boundaries are performed. The Ekman number, the Prandtl number, and the ratio of inner and outer radii are fixed to 10^<-3>, 1, and 0.35, respectively. The magnetic Prandtl number is varied from 5 to 50, and the modified Rayleigh number is increased from 1.5 to 10 times critical. All the obtained successful solutions are weak field-dynamo, that is, the total magnetic energy is far less than the total kinetic energy. These solutions are characterized by the two-layer spatial structure. The upper layer is governed by prograde strong zonal flows and less-organized prograde propagating spiral convection vortices, while the lower layer is dominated by turbulent retrograde propagating columnar convection vortices. The strong zonal flow in the upper layer prevents the magnetic field generated in the lower layer from penetrating to the outer surface., 日本流体力学会, Japanese

213 惑星系最初期進化におけるダスト衝突破壊過程の重要性(オーラルセッション7 分子雲・原始惑星系円盤)
福井 隆, 田中 秀和, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2009, 41, 41, 28 Sep. 2009
日本惑星科学会, Japanese

318 水星の表面温度分布 : 熱構造への示唆(オーラルセッション11 固体天体の科学・惑星探査II)
岩堀 智子, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2009, 69, 69, 28 Sep. 2009
日本惑星科学会, Japanese

207 Scientific Objectives and the Present Status of SELENE-2 Lunar Landing Mission
TANAKA Satoshi, IIJIMA Yu-ichi, Mitani Takefumi, Ohtake Hisashi, Ogawa Kazunori, Kimura Jun, Kuramoto Kiyoshi, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 2009, 35, 35, 28 Sep. 2009
現在、JAXAでは「かぐや」に続く月探査計画として月惑星への着陸および移動探査技術の獲得を主目的としたSELENE-2計画を検討している。日本地球惑星科学連合2009年大会(5月)では、本ミッションの科学目標、搭載機器候補現状、そしてミッションスケジュールの概略について述べた。本講演では連合大会時に発表した予定案も踏まえ、検討進行状況について報告する。, The Japanese Society for Planetary Sciences, Japanese

208 Scientific Objectives of SELENE-2 Project
Tanaka Satoshi, Iijima Yu-ichi, Otake Hisashi, Kimura Jun, Kuramoto Kiyoshi, Mitani Takefumi, Ogawa Kazunori, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 2009, 36, 36, 28 Sep. 2009
The next lunar exploration project, 'SELENE-2' is being planned as a successor to 'KAGUYA'. SELENE-2. The mission science objectives being updated are categorized into two groups. The first one is related to identification of the Moon-forming material, and the second one is related to clarification of the relationship between surface dichotomy and deeper structure. In this talk, we report the current status and the science scenario of the mission., The Japanese Society for Planetary Sciences, Japanese

MELOS火星複合探査の科学検討 火星気象学,あるいは水文学への挑戦
今村剛, 笠井康子, 佐川英夫, 黒田剛史, 佐藤毅彦, 上野宗孝, 鈴木睦, 高橋幸弘, 高橋芳幸, はしもと じょーじ, 倉本圭, 日本惑星科学会誌 遊・星・人, 18, 2, 76, 78, 25 Jun. 2009
Japanese

Origin, Evolution, and Diversities of Habitable Planets
KURAMOTO Kiyoshi, ABE Yutaka, HASHIMOTO George, HAYASHI Yoshi-Yuki, SEKINE Yasuhito, SATO Mitsuteru, The astronomical herald, 102, 3, 184, 189, 20 Feb. 2009
日本天文学会, Japanese

Origin, Evolution, and Diversities of Habitable Planets
KURAMOTO Kiyoshi, ABE Yutaka, HASHIMOTO George, HAYASHI Yoshi-Yuki, SEKINE Yasuhito, SATO Mitsuteru, The astronomical herald, 102, 3, 184, 189, 20 Feb. 2009
日本天文学会, Japanese

月の初期分化と熱進化
倉本圭, 日本鉱物科学会年会講演要旨集, 2009, 0, 21, 20, 2009
Redistribution of radiogenic elements likely plays key roles on the long-term thermal evolution of the Moon. Their transport to the lunar shallow layer and deep interior is required for the rapid cooling of lunar lithosphere and for the late heating of lunar interior inducing mare volcanism, respectively. The overturn of unstably stratified cumulate mantle under the Earth's tidal effect may be responsible for the asymmetry in volcanism and radiogenic element distribution between the near side and the far side of the moon., 一般社団法人日本鉱物科学会, Japanese

Scientific Objectives of SELENE-2 Project
Tanaka Satoshi, Iijima Yu-ichi, Otake Hisashi, Kimura Jun, Kuramoto Kiyoshi, Mitani Takefumi, Ogawa Kazunori, Abstracts of Annual Meeting of the Geochemical Society of Japan, 56, 0, 84, 84, 2009
本年6月に運用を終了した月周回衛星「かぐや」に続く月探査計画として，JAXAでは月惑星への着陸および移動探査技術の獲得を主目的としたSELENE-2 計画を検討している．本計画は 1) 着陸・移動・長期滞在技術の開発と実証，2) その場観測による月表面物質の科学探査と月の利用可能性調査，3) 国際貢献と国際的地位の確保，をコンセプトとし，2010 年代半ばまでの打ち上げを目指す．本講演ではSELENE-2の科学目標や科学搭載機器についての現在の検討状況と，今後の予定について報告する．, GEOCHEMICAL SOCIETY OF JAPAN, Japanese

次期月探査計画SELENE‐2で目指すサイエンス
田中智, 飯島祐一, 大嶽久志, 木村淳, 倉本圭, 三谷烈史, 小川和律, 日本鉱物科学会年会講演要旨集, 2009, 0, 29, 28, 2009
The next lunar exploration project, &lsquo SELENE-2&rsquo is being planned as a successor to &lsquo KAGUYA &rsquo. SELENE-2. The mission science objectives being updated are categorized into two groups. The first one is related to identification of the Moon-forming material, and the second one is related to clarification of the relationship between surface dichotomy and deeper structure. In this talk, we report the current status and the science scenario of the mission., 一般社団法人日本鉱物科学会, Japanese

同期回転惑星大気における循環構造
石渡正樹, 中島健介, 森川靖大, 高橋芳幸, 小高正嗣, 倉本圭, 林祥介, 大気圏シンポジウム・講演集(Web), 23rd, V-5 (WEB ONLY), 2009
Japanese

The effects of the upper mechanical boundary condition on MHD dynamo solutions in a rotating spherical shell
SASAKI Youhei, Takehiro Shin-ichi, Hayashi Yoshi-Yuki, Kuramoto Kiyoshi, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2009, 106, 106, 2009
Numerical experiments of magnetohydrodynamic (MHD) dynamos driven by thermal convection in a rotating spherical shell with a free-slip top boundary and a no-slip bottom boundary are performed. The Ekman number, the Prandtl number and the ratio of inner and outer radii are fixed to 10^<-3>, 1, and 0.35, respectively. The magnetic Prandtl number Pm is varied from 1 to 50. The modified Rayleigh number Ra is increased up to 15 times the critical value Ra_c. MHD calculations are carried out from non-magnetic thermal convection solutions with a weak dipole magnetic field on top of them, and dynamo solutions are obtained when Ra≥1.87Ra_c and Pm≥4. The strong prograde zonal flows in the non-magnetic solutions disappear in the dynamo solutions as the evolution of magnetic fields, and slow retrograde zonal flows emerge at the top of the spherical shell. As a result, the omega effect which was expected from the strong zonal flows of the non-magnetic solutions does not operate effectively. All of the obtained dynamo solutions are considered to be categorized as the α^2-type dynamo., 日本流体力学会, Japanese

Early differentiation and thermal evolution of the Moon
Kuramoto Kiyoshi, Abstracts for Annual Meeting of Japan Association of Mineralogical Sciences, 2009, 0, 20, 20, 2009
Redistribution of radiogenic elements likely plays key roles on the long-term thermal evolution of the Moon. Their transport to the lunar shallow layer and deep interior is required for the rapid cooling of lunar lithosphere and for the late heating of lunar interior inducing mare volcanism, respectively. The overturn of unstably stratified cumulate mantle under the Earth's tidal effect may be responsible for the asymmetry in volcanism and radiogenic element distribution between the near side and the far side of the moon., Japan Association of Mineralogical Sciences, Japanese

Scientific Objectives of SELENE-2 Project
Tanaka Satoshi, Iijima Yu-ichi, Otake Hisashi, Kimura Jun, Kuramoto Kiyoshi, Mitani Takefumi, Ogawa Kazunori, Abstracts for Annual Meeting of Japan Association of Mineralogical Sciences, 2009, 0, 28, 28, 2009
The next lunar exploration project, &lsquo SELENE-2&rsquo is being planned as a successor to &lsquo KAGUYA &rsquo. SELENE-2. The mission science objectives being updated are categorized into two groups. The first one is related to identification of the Moon-forming material, and the second one is related to clarification of the relationship between surface dichotomy and deeper structure. In this talk, we report the current status and the science scenario of the mission., Japan Association of Mineralogical Sciences, Japanese

114 P006 ダスト落下を考慮した原始惑星系円盤の固体面密度分布の進化(最優秀発表賞選考,オーラルセッション2,最優秀発表賞選考エントリーポスター,ポスターセッション1)
福井 隆, 田中 秀和, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2008, 14, 14, 01 Nov. 2008
日本惑星科学会, Japanese

107 同期回転惑星大気における循環構造(惑星の形成および惑星大気,オーラルセッション1)
石渡 正樹, 中島 健介, 森川 靖大, 高橋 芳幸, 小高 正嗣, 倉本 圭, 林 祥介, 日本惑星科学会秋期講演会予稿集, 2008, 7, 7, 01 Nov. 2008
日本惑星科学会, Japanese

広帯域ネットワークを基盤とした大学と公開天文台との連携
杉山耕一朗, 小高正嗣, 佐野康男, 大石憲且, 馬場聡, 高井昌彰, 大石尊久, 林祥介, 倉本圭, 渡部重十, 日本惑星科学会誌 遊・星・人, 17, 2, 123, 129, 25 Jun. 2008
Japanese

惑星形成と氷微粒子 氷が担う原始太陽系星雲のグローバル物質輸送
福井隆, 倉本圭, 低温科学, 66, 83, 88, 31 Mar. 2008
Japanese

ダスト落下を考慮した原始惑星系円盤の固体面密度分布の進化
福井隆, 田中秀和, 倉本圭, 日本惑星科学会秋季講演会予稿集, 2008, 14, 2008
Japanese

同期回転惑星大気における循環構造
石渡正樹, 中島健介, 森川靖大, 高橋芳幸, 小高正嗣, 倉本圭, 林祥介, 日本惑星科学会秋季講演会予稿集, 2008, 7, 2008
Japanese

Thermal evolution of Mercury: Effects of bulk composition on core dynamo and global geomorphology
IWAHORI Tomoko, KURAMOTO Kiyoshi, Proceedings of the ISAS Lunar and Planetary Symposium (CD-ROM), 41st, ROMBUNNO.9, 2008
English

MHD dynamo in a rotating spherical shell: Influence of mechanical boundary conditions
SASAKI Youhei, Takehiro Shin-ichi, Hayashi Yoshi-Yuki, Kuramoto Kiyoshi, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2008, 0, 376, 376, 2008
Numerical experiments of magnetohydrodynamic dynamos driven by thermal convection in a rotating spherical shell with a free-slip top boundary and a no-slip bottom boundary are performed. Non-dimensional numbers for the experiments are the modified Rayleigh number Ra=100, the Ekman number E=10^<-3>, the Prandtl number Pr=1, the ratio of inner and outer radii ξ=0.35. The magnetic Prandtl number Pm is varied from 5 to 50. Time integration of non-magnetic thermal convection is carried out until a quasi-steady state is established, and then MHD dynamo calculation is carried out starting from the quasi-steady state with a dipole and toroidal magnetic field. In the non-magnetic thermal convection case, the obtained solution consists of well-organized spiral vortex columns aligned with the rotation axis. A strong prograde zonal flow is produced at the top of the spherical shell in contrast to the simulations with the both no-slip boundaries. In the MHD dynamo cases, calculated magnetic fields fall into decay at all magnetic Prandtl numbers. The strong prograde zonal flow, which is prominent in the case of non-magnetic thermal convection, does not appear, but a slow retrograde zonal flow is produced at the top of spherical shell. As a result, the omega effect expected from the strong zonal flows does not seem to operate effectively., 日本流体力学会, Japanese

月の熱進化の謎
倉本圭, 玄田英典, 荒井朋子, 岡田達明, 杉田精司, 日本惑星科学会誌 遊・星・人, 16, 3, 197, 207, 25 Sep. 2007
Japanese

球殻の厚さを変えた回転球殻熱対流
佐々木洋平, 竹広真一, 倉本圭, 林祥介, 日本流体力学会年会講演アブストラクト集, 2007, 248, 06 Aug. 2007
Japanese

Origin of 17,180-rich materials from ACFER 094
N. Sakamoto, Y. Seto, S. Itoh, K. Kuramoto, K. Fujino, K. Nagashima, A. N. Krot, H. Yurimoto, METEORITICS & PLANETARY SCIENCE, 42, A134, A134, Aug. 2007
WILEY-BLACKWELL, English, Summary international conference

放射によって調節された二酸化炭素氷雲と古火星大気の温室効果
光田千紘, 横畠徳太, 倉本圭, 大気圏シンポジウム, 21st, 1, 4, Jun. 2007
Japanese

太陽系の新しい常識 エウロパの海,イオの火山,タイタンの大気
倉本圭, 科学, 77, 2, 150, 153, 01 Feb. 2007
Japanese

エウロパの海,イオの火山,タイタンの大気 (特集 太陽系の新しい常識)
倉本 圭, 科学, 77, 2, 150, 153, Feb. 2007
岩波書店, Japanese

Radial redistribution of solids in an accreting protoplanetary disk: Constraints from textural and compositional properties of chondrites
Fukui Takashi, Kuramoto Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2007, 0, 25, 25, 2007
Oxygen isotopic heterogeneity among chondritic constituents (¹⁶O-rich CAIs and ¹⁶O-poor chondrules) reflects evolution in oxygen isotopic composition of the inner solar nebula gas. Yurimoto and Kuramoto (2004) have suggested that the oxygen isotopic evolution at the inner nebula was induced by subsequent enhancement of ¹⁶O-depleted H₂O which produced by photochemical process in the parent molecular cloud. In their model, the excess H₂O was supplied from outer part of the nebula with inward migration of ice-covered dust particles and evaporation of the icy mantle. However, they did not consider migration of silicate dust particles which apparently result in depletion of chondrule precursors.
In this study, we perform a numerical simulation of radial transport of H₂O and silicate in a turbulent protoplanetary disk considering difference in adhesive properties between H₂O ice and silicate. As a result, sticky ice-covered dust particles grow up to ~cm and efficiently migrate inward supplying excess water vapor to the inner nebula, while small (~sub-mm) silicate particles are well coupled to the nebula gas and retained in the inner nebula over ~Myr., THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Japanese

Scattering greenhouse effect of radiatively adjusted CO2 ice clouds
Mitsuda Chihiro, Yokohata Tokuta, Kuramoto Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2007, 0, 143, 143, 2007
The scattering greenhouse effect of a CO₂ ice cloud layer may expand the outer edge of the habitable zone in which a terrestrial planet have warm and wet climate. This study explores how the scattering greenhouse effect depends on the planetary mass or surface gravity by using a CO₂-H₂O atmosphere model taking into account the radiative adjustment processes for CO₂2 ice cloud profile. For a planet with the surface gravity and solar flux equivalent to those of paleo-Mars at 3.8Ga, a CO₂ ice cloud layer which can cause strong greenhouse effect is possibly formed. In this case, the global mean surface temperature rises above the melting point of H₂O when the surface pressure is larger than 3 bar and the mixing ratio of cloud condensation nuclei is kept within the range 10⁶ - 10⁷ kg^-1. As the surface gravity increases, the atmospheric pressure required for such warm climate tends to increase., THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Japanese

Thermal history of a Mercury with radioactive elements concentrated in a crust
Iwahori Tomoko, Hirose Yusuke, Kuramoto Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2007, 0, 44, 44, 2007
We examine the effect of mantle heat source distribution on the thermal evolution of Mercury. The radioactive elements, which are incompatible elements, are likely to be enriched in the crust. While Earth's crustal material partly returns to the mantle by the plate motion, Mercury's crustal elements are likely to be retained because of the lack of plate motion. This implies that Mercury's mantle has less heat sources and secular cooling may be more efficient. We calculate Mercury's thermalhistory by using mixing length theory and compare the highlydifferentiated mantle model with the homogeneous mantle model., THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Japanese

同期回転惑星の大気大循環の数値計算
石渡正樹, 中島健介, 森川靖大, 高橋芳幸, 小高正嗣, 倉本圭, 林祥介, 日本惑星科学会秋季講演会予稿集, 2007, 95, 2007
Japanese

大気 大気と地球環境
倉本圭, Re, 153, 5, 9, 01 Jan. 2007
Japanese

A GCM experiment on an atmosphere of a synchronously rotating planet.
Ishiwatari Masaki, Nakajima Kensuke, Morikawa Yasuhiro, Takahashi Yoshiyuki, Odaka Masatsugu, Kuramoto Kiyoshi, Hayashi Yoshi-yuki, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2007, 0, 95, 95, 2007
Extrasolar planets near stars is considered to rotatesynchronously due to strong tidal force. On a synchronously rotating planet, one side is permanentlyilluminated while the other side is in perpetual darkness. Joshi et al. (1997) performs an atmospheric GCM simulation on a synchronouslyrotating planet, but their model does not contain hydrologic processes. In this study, a GCM experiment is performed fora moist atmosphere on a synchronously rotating planet, and atmospheric circulation and heat transport are examined. The results indicate thatlongitudinal heat transport in the low latitudinal region is caused by propagation of equatorial Kelvin and Rossby waves,and that in the higher latitudinal regionis caused by baroclinic eddies., THE JAPANESE SOCIETY FOR PLANETARY SCIENCES

Varying the spherical shell depth in rotating thermal convection
SASAKI Youhei, Takehiro Shin-ichi, Kuramoto Kiyoshi, Hayashi Yoshi-Yuki, 日本流体力学会年会講演論文集, 2007, 248, 248, 2007
For the purpose of investigating possible fluid motion in the Mercury's outer core, the linear stability of convection in a rotating spherical shell is analyzed for various values of shell depth with different mechanical and thermal conditions., 日本流体力学会, Japanese

大気と地球環境 (特集 大気)
倉本 圭, 建築/保全, 28, 3, 5, 9, Jan. 2007
建築保全センター, Japanese

氷が担う原始太陽系星雲のグローバル物質輸送 (宇宙における氷と物質進化) -- (惑星形成と氷微粒子)
福井 隆, 倉本 圭, 低温科学, 66, 83, 88, 2007
2章 惑星形成と氷微粒子, 北海道大学低温科学研究所, Japanese

B306 同期回転惑星の大気大循環の数値計算(スペシャルセッション「さまざまな対流」)
石渡 正樹, 中島 健介, 森川 靖大, 高橋 芳幸, 小高 正嗣, 倉本 圭, 林 祥介, 大会講演予講集, 92, 167, 167, 2007
日本気象学会, Japanese

放射冷却による二酸化炭素氷雲の形成と古火星大気の温室効果
光田千紘, 横畠徳太, 倉本圭, 日本気象学会大会講演予稿集, 90, 84, 30 Sep. 2006
Japanese

木星大気における雲対流
杉山耕一朗, 小高正嗣, 倉本圭, 中島健介, 林祥介, エアロゾル科学・技術研究討論会, 23rd, 219, 220, 08 Aug. 2006
Japanese

Evolution of Oxygen Isotopic Composition and C/O Ratio at Late Stage of Protoplanetary Accretion Disk
FUKUI Takashi, KURAMOTO Kiyoshi, Proceedings of the ISAS Lunar and Planetary Symposium (Institute of Space and Astronautical Science), 38th, 128, 131, Mar. 2006
English

Scattering greenhouse effect of CO₂ ice cloud and climate stability on early Mars
MITSUDA Chihiro, YOKOHATA Tokuta, KURAMOTO Kiyoshi, Proceedings of the ISAS Lunar and Planetary Symposium (Institute of Space and Astronautical Science), 38th, 184, 187, Mar. 2006
English

Vertical structure of CO2 cloud layer and scattering greenhouse effect in early Marian atmosphere
Mitsuda Chihiro, Yokohata Tokuta, Kuramoto Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2006, 0, 67, 67, 2006
The scattering greenhouse effect of a CO₂ ice cloud layer has been proposed as a potential mechanism for keeping the Martian climate warm enough to support flowing water under a faint young Sun. Previous studies have shown that such warm climate is possibly achieved if a cloud layer with optimal ranges of particle size and optical depth is placed in the atmosphere. However, it has not been examined whether or not such an optimal cloud layer could be formed.
In this study, we construct a one dimensional, radiative-convective equilibrium model including cloud formation processes due to radiative cooling and estimate the parameters of cloud layer and the cloud-induced greenhouse effect. Our numerical analysis suggests that a CO₂ ice cloud layer which can cause strong greenhouse effect is formed with achieving both radiative and vapor pressure equilibria, and the global mean surface temperature rises above the melting point of H₂O when the surface pressure is larger than 3 bar and the mixing ratio of cloud condensation nuclei is kept within the range 10⁵ - 10⁷ kg^-1., THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Japanese

Thermal history of a Mercury with reduced composition and the possibility of dynamo in its outer core
Hirose Yusuke, Kuramoto Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2006, 0, 58, 58, 2006
Several lines of evidence such as the reflection spectra of Mercury suggest that Mercury may consist of reduced materials. Therefore, we calculated the Mercury's thermal history assuming that the mantle and the core have the similar compositions to the silicate and metal-sulfide components of enstatite chondrite, respectively. We examined the possibility of the chemical convection in the liquid outer core, caused by the exclusion of light-alloying element associated with inner core growth. If the mantle convection occurs by dislocation creep, the inner core of Mercury does not grow. However, if the mantle convection occurs by diffusion creep and the grain size of mantle is smaller than 3 mm, the inner core grows during 4.5Gyr. In the latter case, the intrinsic magnetic field of Mercury may be explained., THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Japanese

原始惑星系円盤の力学的進化に伴う水の再分配―コンドライト原物質の酸素同位体組成への影響―
福井隆, 倉本圭, 日本惑星科学会秋季講演会予稿集, 2006, 65, 2006
Japanese

Vertical structure and greenhouse effect of radiatively controlled CO₂ cloud layer in a Martian paleoatmosphere
MITSUDA Chihiro, YOKOHATA Tokuta, KURAMOTO Kiyoshi, Proceedings of the ISAS Lunar and Planetary Symposium (CD-ROM), 39th, ROMBUNNO.33, 2006
English

Formation of Oxygen Isotopic Heterogeneity among Chondritic Constituents due to Radial Gas‐Dust Fractionation in Protoplanetary Disks
FUKUI Takashi, KURAMOTO Kiyoshi, Proceedings of the ISAS Lunar and Planetary Symposium (CD-ROM), 39th, ROMBUNNO.6, 2006
English

Redistribution of water in an evolving protoplanetary disk:
Fukui Takashi, Kuramoto Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2006, 0, 47, 47, 2006
Oxygen isotopic composition of chondritic constituents(CAIs and chondrules) implies the existence of ¹⁶O-rich/¹⁷O- and ¹⁸O-rich oxygen reservoirs and the mechanicalmixing of them with various mixing ratio in the solarnebula. Recent studies suggest that CO self-shieldingeffect in parent molecular clouds produces the ¹⁶O-rich CO gas and ¹⁷O- and ¹⁸O-rich H₂O ice.In this study, the mixing process of these reservoirsand its effect on the oxygen isotopic composition ofprotoplanetary accretion disks are proposed. Due to thepreferential dust transport in an accretion disk,¹⁷O- and ¹⁸O-rich H₂O vapor enriches inside thesnow line. The degree of enrichment increases with decayof T Tauri accretion, following that the oxygen isotopiccomposition of the inner disk gradually evolves from¹⁶O-rich to ¹⁷O- and ¹⁸O-rich. We numerically simulateabove processes for the main oxygen reservoirs includingH₂O and silicate, and follow the oxygen isotopicevolution quantitatively. Results are compared with theisotopic and chronological analysis of CAIs and chondrulesto clarify the oxygen isotopic evolution in the solar nebula., THE JAPANESE SOCIETY FOR PLANETARY SCIENCES

A361 放射冷却による二酸化炭素氷雲の形成と古火星大気の温室効果(スペシャルセッション「惑星大気の科学」II)
光田 千紘, 横畠 徳太, 倉本 圭, 大会講演予講集, 90, 84, 84, 2006
日本気象学会, Japanese

Origin of the Fractionation in Hydrogen and Oxygen Isotopes Molecular cloud origin hypothesis for the Oxygen isotopic heterogeneity in the solar system
倉本圭, ゆり本尚義, 日本惑星科学会誌 遊・星・人, 14, 4, 193, 200, 25 Dec. 2005
日本惑星科学会, Japanese

二酸化炭素氷雲の散乱温室効果による古火星気候の温暖化
光田千紘, 横畠徳太, 倉本圭, 日本気象学会大会講演予稿集, 88, 321, 31 Oct. 2005
Japanese

木星大気対流圏における静的安定度の水存在量に対する依存性
杉山耕一朗, 小高正嗣, 倉本圭, 林祥介, 日本気象学会大会講演予稿集, 88, 417, 31 Oct. 2005
Japanese

月の内部構造と熱的進化
倉本圭, 日本地震学会秋季大会講演予稿集, 2005, 7, 01 Oct. 2005
Japanese

「轟きは夢をのせて-喜・怒・哀・楽の宇宙日記」, 的川泰宣著, 共立出版, 総366頁, ISBN 4-320-00566-X, 定価本体1,900円+税
倉本 圭, 遊・星・人 : 日本惑星科学会誌, 14, 2, 71, 71, 25 Jun. 2005
日本惑星科学会, Japanese

地球科学 惑星としての地球
倉本圭, 学術月報, 58, 3, 180, 184, 15 Mar. 2005
Japanese

惑星としての地球 (特集:地球科学)
倉本 圭, 学術月報, 58, 3, 180, 184, Mar. 2005
日本学術振興会, Japanese

Evolution of the surface environment on Mars : Role of the CO_2 atmosphere, ice caps, and clouds(Mars and Titan, International Symposium on Origins of Life and Astrobiology) :
Yokohata Tokuta, Mitsuda Chihiro, Kuramoto Kiyoshi, Viva origino, 33, 2, 75, 75, 2005
文部省科学研究費総合研究(B)「原始地球上における生命の起源に関する研究」班, English

エンスタタイト的な組成を仮定した水星の熱史
広瀬佑介, 倉本圭, 日本惑星科学会秋季講演会予稿集, 2005, 69, 2005
Japanese

Redox and thermal state of Io
HIYAMA Katsuaki, KURAMOTO Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2005, 0, 112, 112, 2005
Since the building blocks of the Galilean satellites likely experience the chemical interaction with H₂O in the circum-jovian nebula, they would have strongly oxidized composition. Here we revisit the model of internal structure and composition of Io taking into account highly oxidized materials. For the solar mixture of major rock-forming elements, the mineral combination has been calculated taking the content of O as a parameter. The minerals are distributed to the crust, mantle and core. The moment of inertia factor is calculated from their mass ratio and average densities. The composition of Io that explains the average density has the core with magnetite (66 wt %) and troilite (32 wt%), mantle with pyroxene (Mg# = 97) and crust with MgSO₄ (66 wt %) and feldspar (30 wt %). These spheres occupy 34, 43 and 24 wt % of the total mass of Io, respectively. We focus on the large amount of MgSO₄ and calculate the chemical equilibrium of MgSO₄=MgO+SO₂+ 1/2 O₂ in the circum-jovian nebula. The existence of MgSO₄ existence requires a fractionated region with low-T, high-SO₂ pressure in the circum-jovian nebula. We also discuss the thermal structure of Io and stability of MgSO₄ in the crust., THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Japanese

原始タイタンH₂大気の流体力学的散逸
中神雄一, 倉本圭, 日本惑星科学会秋季講演会予稿集, 2005, 97, 2005
Japanese

CO2 ice clouds induced warming of early Martian climate and its stability
Mitsuda Chihiro, Yokohata Tokuda, Kuramoto Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2005, 0, 94, 94, 2005
The scattering greenhouse effect of CO₂ ice clouds is proposed as a mechanism to make the Martian climate warm enough to support flowing water under a faint young Sun. Previous studies have shown that such warm climate is possibly achieved if a cloud layer with suitable ranges of particle size and optical depth is given. However, it has not been examined whether or not such a suitable cloud layer could exist stably in the early Martian atmosphere. In this study, we construct a 1-D radiative model for the CO₂-H₂O atmosphere and analyze cloud stability on the basis of the numerical estimation of the ice condensation or evaporation rate in a cloud layer. We assume that the latent heat release of CO₂ condensation is balanced with the radiative cooling in cloud layer. Our numerical analysis suggests that a CO₂ ice cloud layer is stabilized and the global mean surface temperature rises above melting point of H₂O when the atmospheric pressure is larger than 1 bar and the number column density of cloud condensation nuclei is fixed at nearby 10¹⁰ m^-2., THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Japanese

二酸化炭素氷雲による初期火星の温暖化:液体の水は存在可能か?
光田千紘, 横畠徳太, 倉本圭, 大気圏シンポジウム, 19th, 190, 193, 2005
Japanese

Thermal history of a Mercury with enstatite chondoritic composition
HIROSE Yusuke, KURAMOTO Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2005, 0, 69, 69, 2005
Mercury, the nearest planet from the Sun, may consist of reduced materials like enstatite chondrite (Wasson 1988).The parameterized convection theory is employed to calculate the Mercury's thermal history,assuming that the mantle and core have the similar compositions to the silicate and metal-sulfur components of enstatite chondrite, respectively. Our result suggests that the present inner core of Mercury is significantly smaller than the previous studies., THE JAPANESE SOCIETY FOR PLANETARY SCIENCES

The hydrodynamic escape from Titan's H2 proto-atmosphere
Nakagami Yuuichi, Kuramoto Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2005, 0, 97, 97, 2005
It is likely that proto-Titan accumulated hydrogen molecules from the Saturnian subnebnula and kept a proto-atmosphere with surface pressure of several hundred bars. Once the subnebula began to dissipate, this proto-atmosphere should have escaped as the pressure of the astmosphere decreased at the upper boundary. We have developed a numerical hydrodynamic model similar to that for solar wind, and solved the escape of the proto-atmosphere. If the density of the subnebula becomes less than that of the atmosphere with factor of 10^-1, the intense escape occurs and could lose the almost all of the proto-atmosphere for several hundred years. We also argue the effects of the such vigorous escape on the composition of the unescaped atmospheric components., THE JAPANESE SOCIETY FOR PLANETARY SCIENCES

P324 木星大気対流圏における静的安定度の水存在量に対する依存性
杉山 耕一朗, 小高 正嗣, 倉本 圭, 林 祥介, 大会講演予講集, 88, 417, 417, 2005
日本気象学会, Japanese

P124 二酸化炭素氷雲の散乱温室効果による古火星気候の温暖化
光田 千紘, 横畠 徳太, 倉本 圭, 大会講演予講集, 88, 321, 321, 2005
日本気象学会, Japanese

『進化する地球惑星システム』, 東京大学地球惑星システム科学講座[編]東京大学出版会, 全236ページ, 定価2500円+税, ISBN4-13-063703-7
倉本 圭, 遊・星・人 : 日本惑星科学会誌, 13, 4, 264, 265, 25 Dec. 2004
日本惑星科学会, Japanese

Hokkaido Univ. LOC(Report of the JSPS 2004 fall meeting)
倉本 圭, Planetary People, 13, 4, 262, 263, 25 Dec. 2004
The Japanese Society for Planetary Sciences, Japanese

『進化する地球惑星システム』
倉本 圭, 遊・星・人 : 日本惑星科学会誌, 13, 3, 188, 189, 25 Sep. 2004
日本惑星科学会, Japanese

タイタン大気の起源と進化―同位体比の考察から―
中神雄一, 倉本圭, 大気圏シンポジウム, 18th, 34, 37, 2004
Japanese

Growth and Migration of Dust in the Jovian Subnebula : Investigation of the Possibility of Satellitesimals Formation
Fukui Takashi, Shimazawa Ryuhei, Kuramoto Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2004, 0, 65, 65, 2004
We study processes of dust growth in the Jovian subnebula, the first stage of the Galilean satellite formation. To form satellitesimals, the time of dust growth is shorter than that of dust falling to Jupiter. We perform a numerical calculation for the growth time taking into account the effect of imperfect sticking. Comparing it to the falling time, we discuss the possibility of satellitesimals formation. The result indicates that the formation is difficult without considering the effect of dust concentration or the mechanism to increase critical velocity for sticking., THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Japanese

Proto-atmosphere of Titan - Mass fractionation by hydrodynamic escape of hydrogen atmosphere -
Nakagami Yuuichi, Kuramoto Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2004, 0, 6, 6, 2004
タイタンが周土星系円盤のガスを捕獲することにより水素を主成分とする厚い原始大気を有していた可能性について検討を行った。この原始大気は水素の他にタイタンに集積した天体からもたらされた水蒸気、メタン、アンモニア等を含む。恒星観測から原始太陽からの極端紫外線(EUV) ラックスは現在の 100 倍から 1000 倍に達すると予想されている。タイタン原始大気は、EUV フラックスにより加熱された水素が流体的な散逸を起こし、その際に他の分子も水素と共に散逸した可能性がある。様々な初期組成比を与えて大気構造と散逸による組成分別を求め，現在の大気組成に調和的な原始大気の条件について議論する。, THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Japanese

Stability of CO2 ice clouds and scattering greenohouse effect on early Martian wet atmosphere
Mitsuda Chihiro, Yokohata Tokuta, Kuramoto Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2004, 0, 3, 3, 2004
In order to investigate scattering greenhouse effect of CO₂ ice clouds and those stability against radiative heating on a CO₂-H₂O atmosphere, we constructed a one-dimensional, radiative-convective model. The our calculations suggest that warm and wet climate is possibly induced by the stable cloud layer with visible optical depth about 1.5 when the atmospheric pressure and the radius of cloud particles are fixed 1 atm and 10 micron, respectively., THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Japanese

二酸化炭素の雲による温室効果と火星古環境
横畠徳太, 小杉田圭之, 小高正嗣, 倉本圭, 日本気象学会大会講演予稿集, 83, 83, 391, 391, 21 May 2003
日本気象学会, Japanese

火星気候システムの安定性 大気崩壊と暴走蒸発
横畠徳太, 小高正嗣, 倉本圭, 日本気象学会大会講演予稿集, 83, 83, 58, 58, 21 May 2003
Japanese

P320 二酸化炭素の雲による温室効果と火星古環境
横畠 徳太, 小杉田 圭之, 小高 正嗣, 倉本 圭, 大会講演予講集, 83, 21 May 2003
社団法人日本気象学会, Japanese

火星表層環境進化におけるCO₂凝結の役割
横畠徳太, 小高正嗣, 倉本圭, 大気圏シンポジウム, 17th, 67, 70, 27 Feb. 2003
Japanese

A311 火星気候システムの安定性 : 大気崩壊と暴走蒸発(気候システムII)
横畠 徳太, 小高 正嗣, 倉本 圭, 大会講演予講集, 83, 58, 58, 2003
日本気象学会, Japanese

鉛直対流により励起される火星大気の内部重力波
小高正嗣, 中島健介, 倉本圭, 林祥介, 日本惑星科学会秋季講演会予稿集, 2002, 80, 02 Oct. 2002
Japanese

A possible scenario introducing heterogeneous oxygen isotopic distribution in proto-planetary disks.
H Yurimoto, K Kuramoto, METEORITICS & PLANETARY SCIENCE, 37, 7, A153, A153, Jul. 2002
METEORITICAL SOC, English, Summary international conference

動画と音声を用いた研究公開/教育システムの構築
杉山耕一朗, 中神雄一, 高橋こう子, 島沢竜平, 小高正嗣, 倉本圭, 渡部重十, 林祥介, 日本気象学会大会講演予稿集, 81, 81, 300, 300, May 2002
Japanese

木星型惑星大気の熱力学計算 温度分布と静的安定度の分布
杉山耕一朗, 小高正嗣, 倉本圭, 林祥介, 日本気象学会大会講演予稿集, 81, 81, 207, 207, May 2002
Japanese

鉛直対流により励起される火星大気の内部重力波
小高正嗣, 倉本圭, 中島健介, 林祥介, 日本気象学会大会講演予稿集, 81, 81, 152, 152, May 2002
Japanese

Origin of O isotope anomaly in proto-planetary disk
Yurimoto Hisayoshi, KURAMOTO Kiyoshi, Abstracts of Annual Meeting of the Geochemical Society of Japan, 49, 0, 112, 112, 2002
隕石中の酸素同位体異常の存在から, 原始太陽系星雲中には酸素同位体異常が存在していたことは広く知られているが, その起源については未だに謎である。今回, 分子雲が原始惑星系円盤に進化したとき, 分子雲で発生していた非質量依存性の酸素同位体分別がどのような変化をするのか考察した。その結果, 同位体異常は原始惑星系円盤内部領域において普遍的に起こる現象かもしれないという結果を得た。, GEOCHEMICAL SOCIETY OF JAPAN, Japanese

Scattering Greenhouse Effect of CO2 Ice Clouds and Martian Surface Environment
Yokohata Tokuta, Kosugita Yoshiyuki, Odaka Masatsugu, Kuramoto Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2002, 0, 72, 72, 2002
THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Japanese

Partitioning of CO2 and climate change on Mars
TAKAYAMA Kaoru, YOKOHATA Tokuta, ODAKA Masatugu, KURAMOTO Kiyoshi, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2002, 0, 75, 75, 2002
THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Japanese

A numerical simulation of internal gravity wave generated by thermal convection in the Martian atmosphere
Odaka Masatsugu, Nakajima Kensuke, Kuramoto Kiyoshi, Hayashi Yoshi-Yuki, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2002, 0, 52, 52, 2002
THE JAPANESE SOCIETY FOR PLANETARY SCIENCES

A numerical simulation of internal gravity wave generated by thermal convection in the Martian atmosphere
ODAKA Masatsugu, NAKAJIMA Kensuke, KURAMOTO Kiyoshi, HAYASHI YoshiYuki, 日本流体力学会年会講演論文集, 2002, 84, 85, 2002
A numerical simulation is performed by using a two-dimensional anelastic model for clear sky condition to investigate the possible characteristics of internal gravity waves generated by thermal convection in the Martian atmosphere. The results show that the vertical and horizontal wave length of simulated internal gravity wave are 10km and 10∿ 15km, respectively. The resultant time series show that the vertical phase velocity are about 10m/sec. According to the dispersion relationship of internal gravity wave, the vertical group velocity become about several m/sec. The horizontal mean value of "effective vertical diffusion coefficient", which is the vertical diffusion coefficient when the vertical diffusion is only responsible for the heat flux, has the same order of magnitude of that used by the 1D photochemical model. The result suggests that the internal gravity wave generated by thermal convection in the Martian lower atmosphere contributes to the vertical mixing in the Martian middle atmosphere., 日本流体力学会, Japanese

キーワード気象の事典　　　　　　　　　　　　　　　
朝倉書店, 2002

202 火星大気の安定性と気候変動(セッション2)
横畠 徳太, 小高 正嗣, 倉本 圭, 日本惑星科学会秋期講演会予稿集, 2001, 33, 33, 06 Oct. 2001
In order to study the stability of climate on Mars, we constructed a 2-dimensional energy balance model which includes the atmosphere, regolith, CO_2 polar caps and H_2O ice covers. Longterm CO_2 exchange between the atmosphere and CO_2 polar caps are estimated by investigating the annual amount of CO_2 evaporation and condensation at the polar caps. From our numerical results, a scenario on the evolution of martian climate is proposed., 日本惑星科学会, Japanese

火星大気の安定性と気候変動
横畠徳太, 小高正嗣, 倉本圭, 日本惑星科学会秋季講演会予稿集, 2001, 33, 06 Oct. 2001
Japanese

木星型惑星大気の熱力学計算 大気の静的安定度に関する考察
杉山耕一朗, 小高正嗣, 倉本圭, 林祥介, 日本惑星科学会秋季講演会予稿集, 2001, 39, 06 Oct. 2001
Japanese

208 Thermodynamic Calculation of the atmosphere of the Jovian planets : Consideration of the static stability of the atmosphere
杉山 耕一朗, 小高 正嗣, 倉本 圭, 林 祥介, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 2001, 39, 39, 06 Oct. 2001
An equilibrium thermodynamic calculation method is newly developed to investigate vertical profiles of temperature and condensed species of the Jovian planetary atmospheres. Utilized is the method of minimizing thermodynamic function to obtain equilibrium composition. Its advantage is that we do not have to know the details of corresponding chemical reaction formulae. Assuming ideal gas and ideal solution, the calculation scheme is greatly simplified so that the atmospheric composition can be changed with ease. By use of our new scheme, we demonstrate the dependence of adiabatic lapse rate and static stability on the atmospheric composition., The Japanese Society for Planetary Sciences, Japanese

Climate changes on Mars: CO2 polar cap and H2O ice sheet Tokuta.
横畠徳太, 倉本圭, 日本惑星科学会誌 遊・星・人, 10, 2, 64, 74, 25 Jun. 2001
Japanese

木星型惑星大気の熱力学計算
杉山耕一朗, 小高正嗣, 倉本圭, 林祥介, 日本気象学会大会講演予稿集, 79, 79, 382, 382, 08 May 2001
Japanese

火星気候変動 : CO_2極冠と大気の質量交換
横畠 徳太, 倉本 圭, 小高 正嗣, 渡部 重十, 大会講演予講集, 79, 25, 25, 08 May 2001
Japanese

宇宙の水・地球の水-日本学術会議気象研究連絡委員会主催シンポジウム概要-(1999年11月24日 福岡)
田中 浩, 倉本 圭, 西願寺 善彦, 天気, 47, 11, 801, 803, 30 Nov. 2000
日本気象学会, Japanese

P102 The stability of the Martian atmosphere : mass exchange with the CO_2 polar caps
横畠 徳太, 倉本 圭, 小高 正嗣, 渡部 重十, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 2000, 36, 36, 31 Oct. 2000
The Japanese Society for Planetary Sciences, Japanese

S107 Space Telescpoe for Observation of Planets
高橋 幸弘, 倉本 圭, 今村 剛, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 2000, 85, 85, 31 Oct. 2000
The Japanese Society for Planetary Sciences, Japanese

火星大気の安定性 CO₂極冠との質量交換
横畠徳太, 倉本圭, 小高正嗣, 渡部重十, 日本惑星科学会秋季講演会予稿集, 2000, 36, 31 Oct. 2000
Japanese

惑星観測用宇宙望遠鏡の提案
高橋幸弘, 倉本圭, 今村剛, 日本惑星科学会秋季講演会予稿集, 2000, 85, 31 Oct. 2000
Japanese

謎につつまれた惑星 火星再発見
Ladbury Raymond, 倉本 圭, パリティ, 15, 8, 13, 18, Aug. 2000
丸善, Japanese

Early thermal history of a proto-planet.
千秋博紀, 倉本圭, 松井孝典, 日本惑星科学会誌 遊・星・人, 9, 1, 17, 32, 25 Mar. 2000
Japanese

A opinion poll about future planetary exploration given to students and young scientists
TAKAHASHI Yukihiro, KURAMOTO Kiyoshi, Planetary people, 9, 1, 33, 46, 25 Mar. 2000
The Japanese Society for Planetary Sciences, Japanese

2.エウロパの海(宇宙の水・地球の水 : 日本学術会議気象研究連絡委員会主催シンポジウム概要 : 1999年11月24日 福岡)
倉本 圭, 西願寺 善彦, 山本 哲生, 天気, 47, 11, 801, 802, 2000
日本気象学会, Japanese

P411 Formation of Polar Cap under Martian Paleoenvironment
Yokohata Tokuta, Kuramoto Kiyoshi, Odaka Masatsugu, Watanabe Shigeto, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 1999, 41, 41, 13 Nov. 1999
The Japanese Society for Planetary Sciences, Japanese

火星古環境下における極冠の形成
横畠徳太, 倉本圭, 小高正嗣, 渡部重十, 日本惑星科学会秋季講演会予稿集, 1999, 41, 13 Nov. 1999
Japanese

Planetary Formation and Environment of Primitive Earth
KURAMOTO Kiyoshi, Viva origino, 27, 1, 24, 24, 13 Mar. 1999
Japanese

Continental formation. Elucidation of global material differentiation and circulation process. Chapter 1. What is a continent ? Aqua planet and carbon planet.
倉本圭, 月刊地球, 25, 29, Feb. 1999
Japanese

906 How did the solar nebula produce cosmochemicalfractionation ?
Kuramoto Kiyoshi, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 1998, 44, 44, 13 Oct. 1998
The Japanese Society for Planetary Sciences, English

933 The feasibility study of the Mission to Europa I
O'MINAMI Yuki, MIYAMOTO Hideaki, KURAMOTO Kiyoshi, AKIYAMA Hiroaki, SHIRAISHI Atsushi, HARUYAMA Jun'ichi, TERAZONO Jun-ya, YANO Hajime, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 1998, 71, 71, 13 Oct. 1998
The Japanese Society for Planetary Sciences, Japanese

307 Mission to Europa and Search for Its Possible Biological Evidence
AKIYAMA Hiroaki, SHIRAISHI Atsushi, HARUYAMA Jun'ichi, TERAZONO Jun-ya, YANO Hajime, KURAMOTO Kiyoshi, MIYAMOTO Hideaki, OMINAMI Yuki, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 1998, 91, 91, 13 Oct. 1998
The Japanese Society for Planetary Sciences, Japanese

205 Martian Early Thermal History : Cooling Effect of Impact-Stirring
Senshu Hiroki, Matsui Takafumi, Kuramoto Kiyoshi, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 1998, 77, 77, 13 Oct. 1998
The Japanese Society for Planetary Sciences, Japanese

Feasibility of exploration of lunar iron core ( Prospecting the moon for its origin and evolution)
KURAMOTO Kiyoshi, Planetary people, 7, 3, 218, 220, 25 Sep. 1998
The Japanese Society for Planetary Sciences, Japanese

隕石を作った初期太陽系プロセス--原始惑星系の物質大循環
圦本 尚義, 倉本 圭, 科学, 68, 8, 637, 645,649〜650, Aug. 1998
岩波書店, Japanese

Oscillating magnetic dipole moment of Europa induced by Jovian magnetic field. Possible probe for detecting Europa's ocean.
西願寺善彦, 倉本圭, 山本哲生, 地球惑星科学関連学会合同大会予稿集, 1998, 260, May 1998
Japanese

Martian early thermal history and core formation.
千秋博紀, 松井孝典, 倉本圭, 地球惑星科学関連学会合同大会予稿集, 1998, 56, May 1998
Japanese

Enrichment of O and C and its heterogeneity in solar nebula.
倉本圭, ゆり本尚義, 地球惑星科学関連学会合同大会予稿集, 1998, 256, 257, May 1998
Japanese

"Missing oxygen" problem and degassing-driven evolution of mantle redox state.
倉本圭, 田近英一, 地球惑星科学関連学会合同大会予稿集, 1998, 46, May 1998
Japanese

305 The evolution of Jupiter's magnetic field and the themal history of galilean satelites
SAIGANJI Yoshihiko, KURAMOTO Kiyoshi, YAMAMOTO Tetsuo, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 1997, 37, 37, 15 Sep. 1997
The Japanese Society for Planetary Sciences, Japanese

P415 Material evolution in the solar nebula : Fractionation of C/O ratio due to mass accretion
Kuramoto Kiyoshi, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 1997, 57, 57, 15 Sep. 1997
The Japanese Society for Planetary Sciences, Japanese

Material evolution in the solar nebula: Fractionation of C/O ratio due to mass accretion.
倉本圭, 日本惑星科学会秋季講演会予稿集, 1997, 57, Sep. 1997
Japanese

The evolution of Jupiter's magnetic field and the themal history of galilean satellites.
西願寺善彦, 倉本圭, 山本哲生, 日本惑星科学会秋季講演会予稿集, 1997, 37, Sep. 1997
Japanese

Chemical evolution of proto-atmosphere and mantle during Earth's accretion: role of redox reactions between atmospheric gases and impact ejecta.
千秋博紀, 松井孝典, 倉本圭, 地球惑星科学関連学会合同大会予稿集, 1997, 559, Mar. 1997
Japanese

702 The thermal history and partitioning of H and C during accretion of the Earth
Senshu Hiroki, Matsui Takafumi, Kuramoto Kiyoshi, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 1996, 77, 77, 02 Oct. 1996
The Japanese Society for Planetary Sciences, Japanese

703 Evolution of the redox state of the early Earth's atmosphere and mantle
Kuramoto Kiyoshi, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 1996, 78, 78, 02 Oct. 1996
The Japanese Society for Planetary Sciences, Japanese

Evolution of the redox state of the early Earth's atmosphere and mantle.
倉本圭, 日本惑星科学会秋季講演会予稿集, 1996, 78, Oct. 1996
Japanese

The thermal history and partitioning of H and C during accretion of the Earth.
千秋博紀, 松井孝典, 倉本圭, 日本惑星科学会秋季講演会予稿集, 1996, 77, Oct. 1996
Japanese

Why is the earth water planet ?
倉本圭, 松井孝典, 科学, 66, 3, 193, 201, Mar. 1996
Japanese

Material Evolution of the Solar Nebula. Possible consequences of global dust circulation due to bipolar flow and irradiation of enhanced cosmic rays.
倉本圭, ゆり本尚義, 北神今日子, 奥地拓生, 吉田敬, 平田岳史, 地球惑星科学関連学会合同大会予稿集, 1996, 565, Mar. 1996
Japanese

Earth and Mars. H,C, and Early Differentiation.
倉本圭, 日本惑星科学会誌 遊・星・人, 4, 4, 201, 214, Dec. 1995
Japanese

404 Volatile Loss from the Moon
倉本 圭, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 1995, 404, 404, 13 Nov. 1995
The Japanese Society for Planetary Sciences, Japanese

Volatile Loss from the Moon.
倉本圭, 日本惑星科学会秋季講演会予稿集, 1995, 28, Nov. 1995
Japanese

Early surface environment of Mars; Origin and evolution of the atmosphere.
倉本圭, 田近英一, 松井孝典, 地球惑星科学関連学会合同大会予稿集, 1995, 477, Mar. 1995
Japanese

第２回月の起源研究会集録　　　　　　　　　　　　　　　
宇宙科学研究所, 1995

P06 Mars, A Carbon Rich Planet?
倉本 圭, 松井 孝典, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 1994, P06, 03 Oct. 1994
The Japanese Society for Planetary Sciences, Japanese

Mars, A Carbon Rich Planet?
倉本圭, 松井孝典, 日本惑星科学会秋季講演会予稿集, 1994, 59, Oct. 1994
Japanese

Things wished to be found by MIC.
春山純一, 竹内覚, 倉本圭, 川原琢也, 高橋幸弘, 藤原均, 寺薗淳也, 科学衛星・宇宙観測シンポジウム, 3rd, 212, 215, Oct. 1994
Japanese

The evaporation model of porous ice-dust mixture and its implications to the evolution of comets.
青木雄一郎, 倉本圭, 松井孝典, 地球惑星科学関連学会合同大会予稿集, 1994, 452, Mar. 1994
Japanese

Burial of atmophile elements due to planetesimal impact.
倉本圭, 松井孝典, 地球惑星科学関連学会合同大会予稿集, 1994, 450, Mar. 1994
Japanese

204 A role of core formation in the origin of atmosphere and crust
倉本 圭, 松井 孝典, Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, 1993, 204, 204, 15 Oct. 1993
The Japanese Society for Planetary Sciences, Japanese

海大図鑑
倉本, 圭, 藤倉, 克則
ニュートンプレス, May 2022, 9784315525465, 205p, Japanese

地球大図鑑
倉本, 圭
ニュートンプレス, May 2021, 9784315523737, 205p, Japanese

地球惑星科学入門
在田 一則, 池田 元美, 倉本 圭, 小笹 隆司, 佐藤 光輝, 沢田 健, 白岩 孝行, 杉山 慎, 鈴木 徳行, 高波 鐵夫, 竹下 徹, 谷岡 勇一郎, 池田 隆司, 谷本 陽一, 知北 和久, 角皆 潤, 永井 隆哉, 中川 光弘, 新井田 清信, 長谷部 文雄
北海道大学出版会, 10 Nov. 2010, 4832981951, 427, [Joint work]

地球と生命の進化学―新・自然史科学〈1〉 (新・自然史科学 1)
沢田 健, 西 弘嗣, 栃内 新, 馬渡 峻輔, 綿貫 豊, 秋元 信一, 阿波根 直一, 大原 昌宏, 柁原 宏, 片倉 春雄, 倉本 圭, 小林 快次, 鈴木 徳行, 高橋 英樹, 堀口 健雄, 前川 光司, 増田 道夫, 増田 隆一, 沢田 健, 西 弘嗣, 馬渡 峻輔, 綿貫 豊
北海道大学図書刊行会, 31 Mar. 2008, 4832981838, 272, [Joint work]

宇宙・惑星化学
松田, 准一, 圦本, 尚義, 日本地球化学会, 木多, 紀子, 橘, 省吾, 倉本, 圭, 中村, 智樹, 香内, 晃, 平原, 靖大, 村江, 達士
培風館, Feb. 2008, 9784563049027, vii, 291p, Japanese

Evolution of carbon and nitrogen and generation of prebiotic molecules in the Martian atmosphere
Grants-in-Aid for Scientific Research
01 Apr. 2022 - 31 Mar. 2027
寺田 直樹, 古川 善博, 黒田 剛史, 三宅 洋平, 関 華奈子, 青木 翔平, 横田 勝一郎, 倉本 圭
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Tohoku University, 22H00164

地球流体力学的アプローチによる木星型惑星大気の研究
科学研究費助成事業 基盤研究(B)
01 Apr. 2021 - 31 Mar. 2025
竹広 真一, 高橋 芳幸, 中島 健介, 倉本 圭, 佐藤 隆雄, 杉山 耕一朗
今年度は, 木星型惑星大気の表層ジェット生成のメカニズムの研究に用いられいる「浅いモデル」と「深いモデル」の 2 系統のモデルについて, 数値実験の設計と系統的なパラメター数値実験のための予備的なテスト計算を行った.
「浅いモデル」は当初予定していた惑星表面の薄い大気層の 3 次元流体運動を考えたモデルに取り掛かる準備として, 回転球面上の 1 層浅水モデルに小規模対流運動の効果を表す渦度強制を導入してパラメター実験を行った. この数値実験の先行研究である Scott and Polvani (2008) の設定をもとに, モデル解像度を高く, 渦度強制スケールを小さくしたところ, 木星および土星大気にみられるような赤道域の強い順行ジェットと中高緯度域の弱い縞状構造が出現する状況が見出された. このモデルでのパラメター実験は, 今後の3 次元モデルによる数値実験での木星土星大気に相当するようなパラメターを制限する際に役立つと期待される.
「深いモデル実験」は Heimpel and Aurnou (2007) の設定に基づいて, 研究代表者が開発し研究してきた地球流体電脳倶楽部の回転球殻熱対流モデル(http://www.gfd‐dennou.org/library/spmodel/) を用いて, 経度方向の対称性を仮定せず計算領域を全球に広げ, 粘性拡散係数を高次で増加させるパラメターをさまざまに変化させて時間積分を行った. その結果, Heimpel らが見出した, 木星土星大気にみられる赤道順行ジェットと中高緯度縞状ジェットが出現するのは高次の粘性が強い設定の場合のみであり, 高次粘性効果を弱めていくと中高緯度の縞状ジェットが消失してしまうことが見出された.
日本学術振興会, 基盤研究(B), 京都大学, 21H01155

Evolution of early-Earth atmophere with reduced chemical compositions
Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
01 Apr. 2021 - 31 Mar. 2024
倉本 圭
[揮発性物質の原始大気・惑星内部分配モデルの構築]マグマオーシャン、金属鉄、富水素原始大気間の水素、炭素等の揮発性元素の分配を、原始惑星の集積成長過程と同時に解く数値シミュレーションコードの開発を進めた。近年の地震学的探査によって理解が急速に進展している火星内部の揮発性物質量と対比できるアウトプットを得つつある。
[多成分大気散逸モデルの拡張]新たにH2Oとその光化学生成物を放射冷却材として加えた流体力学的散逸モデルを構築した。モデル計算の結果、放射活性の高いH2Oならびにその光分解生成物にも、その放射冷却効果によって原始大気からの水素流出を大幅に抑制する働きがあることが明らかになってきた。これは還元的原始大気が、惑星集積期を含め数億年の時間スケールで持続しうることを示す。
[原始大気海洋系の化学進化モデルの構築]光化学過程と水溶液反応に駆動される、原始大気-原始海洋の結合進化モデルのひな型を構築した。富水素大気から出発した場合、非水溶性の高分子炭化水素が大量に生じ、原始海洋表層に油質層を形成する可能性が明らかになってきた。また、NH3の貯蔵庫としての海洋の役割について理論的に解析を進めた。炭酸塩との化学平衡状態にある海洋を想定すると、NH4+を含む溶存NH3量は気相中のNH3量を大幅に上回りうることが分かった。これは原始地球表層でアミノ酸の無生物学的な合成が可能とされる大気NH3分圧レベルが、従来の大気光化学モデルからの推定よりも大幅に伸びる可能性を示している。
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 21K03638

Modeling of water and material circulations in the solar system objects
Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
30 Jun. 2017 - 31 Mar. 2022
玄田 英典, 高橋 芳幸, 鎌田 俊一, 倉本 圭, 黒川 宏之, 市川 浩樹
本研究では、太陽系天体における水・物質循環に関する実証可能な物理モデルを構築し、多様な水環境を有する太陽系天体が、いかにして作られたのかを明らかにする。最終的には、実験班により定量化された化学過程を、各天体の物理モデルに組み込み、探査・分析データを実証として、太陽系天体の水・物質循環の歴史を紐解くことを目的とする。
多様な小天体の水・揮発性元素量解明を目的とし、小天体内部の水岩石反応から予想される鉱物組み合わせに対して理論スペクトル計算を行い、近赤外リモセンデータから母天体組成を制約する理論的枠組みを構築した。また、衝突計算を行い、リュウグウを形成した母天体の破壊的な衝突によって一部の含水鉱物が脱水するが、一部は生き残ることを明らかにした。はやぶさ２に続くミッションである火星衛星探査計画も推進している。
氷天体の内部海の維持に関しては、特に冥王星を対象にした研究を進めた。ガスハイドレートの薄い層が内部海の凍結を防ぐことがわかった。同時に、巨大盆地の安定性や、窒素に富む表層などといった冥王星の謎も解明できることを明らかにした。
金星の大気大循環モデル実験および、古火星大気を想定した大気放射モデルの構築を行った。金星大気実験からは、金星探査機あかつきが発見した惑星規模筋状構造の成因を明らかにした。火星に関しては、酸化的大気組成下での太古の流水活動を示す火星探査データを受け、過酸化水素による温暖化機構を提唱した。
地球型惑星の大気と水の起源解明を目的とし、揮発性元素供給・分配・散逸の理論モデル構築を行った。その成果として、原始惑星円盤内のダスト進化・小天体組成に応じた初期惑星の水量・大気組成の予想が可能となった。また、集積期の火星大気形成と進化を、脱ガス成分と原始太陽系星雲ガス成分の成層性を考慮し、含水素大気の長寿命化の可能性を示した。
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area), Tokyo Institute of Technology, 17H06457

Formation and evolution of a reduced-type proto-atmosphere on early Earth
Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
01 Apr. 2018 - 31 Mar. 2021
Kuramoto Kiyoshi
Taking into account updated constraints for the composition of Earth's building blocks, a new theoretical study has been conducted to clarify the formation and evolution of the primordial atmosphere on Earth. The new model shows that impact degassing from iron-containing building blocks releases chemically reduced molecules rich in hydrogen and methane. In the early stages of Earth's accretion, gas from the solar nebula may have also been mixed into the primordial atmosphere. Our numerical simulations of atmospheric escape to space accurately include the processes of heat loss, indicating that hydrogen is leaking into space much more slowly than previously expected. This, together with the isotopic constraints on volatile elements in the Earth and primitive meteorites, suggests that a reducing atmosphere, known to be an effective site for prebiotic chemical evolution, was maintained for millions of years, including the time of the emergence of life.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 18K03719

太陽系外惑星の新機軸：地球型惑星へ
科学研究費助成事業 新学術領域研究(研究領域提案型)
01 Apr. 2016 - 31 Mar. 2017
林 正彦, 倉本 圭, 百瀬 宗武, 井田 茂, 左近 樹
これまでの新学術領域研究5年の取りまとめとして、計画研究代表者及び公募研究代表者のすべてから研究成果に関する情報を包括的に収集し、最終的に研究成果報告書（冊子体）を作成した。
得られた成果をさらに今後の系外惑星研究に生かしていきたい。
日本学術振興会, 新学術領域研究(研究領域提案型), 国立天文台, 16H01702

New Frontiers of Extrasolar Planets: Exploring Terrestrial Planets
Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
01 Apr. 2011 - 31 Mar. 2016
HAYASHI Masahiko
The managing team had an objective to promote the four pre-planned areas of research under close interaction one another. We encouraged active exchange of information among the researchers involved in this Grant-in-aid program, and organized nine international conferences with more than 800 participants in total. We also build a homepage dedicated for the program and released information and achievements to both inside and outside of the country. We worked to foster younger generation researchers by involving graduate students and hiring posdocs with the Grant. We approved a total of 14 open research proposals in two times, with the proposed researchers spreading over many Japanese universities and research organizations.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area), 23103001

Modelling and theoretical study for exoplanet atmospheres
Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
01 Apr. 2011 - 31 Mar. 2016
Kuramoto Kiyoshi, ISHIWATARI Masaki, GENDA Hidenori, TAKEHIRO Shinichi, SASAKI Yohei, NAKAJIMA Kensuke, HAMANO Keiko, ONISHI Masanori
Evolution of steam atmospheres on earth-like planets after each final giant impact event is theoretically solved with an analysis of its observability. Two types of evolutionary tracks are found: one is the rapid formation of a water ocean and another is the long-term persistence of the magma ocean state. The secular loss of surface water due to atmospheric escape driven by stellar UV irradiation may rather stabilize surface liquid water than merely produce an arid surface environment. General circulation experiments provided with various boundary conditions reveal that a synchronously rotating planet and a land planet may have wider habitable zones than previously thought. Numerical models to solve cloud convection and radiative transfer in gas giant planets are also developed, revealing the mechanisms for the intermittencies observed for cloud convection in the solar system gas planets as well as roles of cloud layers on controlling the thermal emission from gas giant atmospheres.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area), Hokkaido University, Principal investigator, Competitive research funding, 23103003

Theoretical study on mantle overturn processes in the moon and small rocky planets.
Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
2010 - 2012
KURAMOTO Kiyoshi, TAKEHIRO Shin-ichi, FUKUI Takashi, ADACHI Toshitaka
Theoretical and numerical studies on the evolution of the interiors of the Moon and small rocky planets were performed on the basis of the consideration about the variety of raw materials of these bodies by using a model of proto-planetary disk. A series of cumulate rock layers, formed in the early Moon due to cooling and solidification of a magma ocean, should have overturned toward stable structure. During the overturn process, Mg-rich olivine cumulate likely becomes to melt again, which is consistent with the exposure of Mg-rich mafic minerals on the lunar far-side. The present moment of inertia factor of the Moon is explained by the density profile after the completion of overturn. Recent spacecraft data shows that Mercury has a significantly reduced composition enriched in sulfur as well as E-chondrites, which is consistent with our disk model, and also has a thin silicate mantle with thickness less than about 400 km. We performed thermal history simulations considering such a new structure. It is suggested that the liquid core of Mercury is thermally convective until present, allowing dynamo action producing the intrinsic magnetic field of Mercury.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, Principal investigator, Competitive research funding, 22540427

A numerical study on climates of synchronously rotating terrestrial planets
Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
2008 - 2011
ISHIWATARI Masaki, KURAMOTO Kiyoshi, ODAKA Masatsugu, NAKAJIMA Kensuke
In this study, parameter experiments on structures of moist atmospheres on synchronously rotating planets are performed, and model infrastructure needed for realistic simulations are developed. Parameter experiment with various planetary rotation rate show existence of oscillating north-south asymmetric states and occurence of multiple equilibrium. Parameter experiment with various solar constant show that the value of solar constant at which the runaway greenhouse states occur changes about 100W/m^2 according to the value of planetary rotation rate. Moreover, radiation scheme for hydrogen atmospheres and a data input/output library are developed.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 20540223

Re-examination of the thermal history of Mercury and the origin of its intrinsic magnetic field
Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
2007 - 2009
KURAMOTO Kiyoshi, SASAKI Youhei, FUKUI Takashi, IWAHORI Tomoko
The bulk composition of Mercury estimated from a model for the solar nebula evolution is adopted for the numerical and theoretical analysis of the thermal history and dynamo action of this innermost planet. The mantle components are probably more viscous than the previous estimates, which slows down the growth of solid inner core. The release of light element from the slowly growing inner core possibly induces the convection of outer liquid core with generating a moderate dynamo action and the present weak intrinsic magnetic field. These results provide a basis for the interpretation of data acquired by the current and future Mercury exploration missions.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, Principal investigator, Competitive research funding, 19540433

同位体による先太陽系史と太陽系創成期の解明
科学研究費助成事業 基盤研究(S)
2005 - 2008
圦本 尚義, 榎森 啓元, 倉本 圭
最近,申請者達は『太陽系固体惑星の起源物質(Nature 428,921:2004)』,『酸素同位体的に不均一な太陽系の謎(Science 305,1763:2004)』,『太陽系の形成順序(Nature 423,728;2003)』を解明する重要な発見や仮説を提唱し,太陽系の新しい起源論を展開し始めた。本研究では,これらの発見に対応する太陽系創成期とそれに直接つながる先太陽系史に焦点を当て,これらの発見を進展させるための新しい証拠を隕石から探索する。この探索結果を取り入れ,現在提唱中の仮説を検証・発展させることにより新しい太陽系起源論を構築することを目的とする。
今年度は以下の研究を行い,今年度より採択された特別推進研究に研究を発展させた。
●隕石中における先太陽系物質の系統的な探査
1.同位体顕微鏡を用いて隕石研磨片のマトリックス中の同位体異常を精査した。
2.同位体異常があった領域を電界放出型走査電子顕微鏡によりナノメートル分解能で観察し,同位体異常を持つ物質を同定した。
3.同定粒子を現有の分析走査電子顕微鏡により化学分析し,鉱物名と組成を決定した。
4.隕石の種類毎に先太陽系物質の特徴および存在度についてデータベースを作成した。
●太陽系内の酸素同位体異常の起源と大きさ
1.隕石試料の中に含まれている46億年前の太陽風成分酸素の同位体比を同位体顕微鏡により測定した。
2.測定値に数値計算による補正を加え,46億年前誕生時の太陽の酸素同位体比を決定した。
●始原隕石構成物質の形成と進化
1.先太陽系物質の系統的な探査のため作成した隕石試料から難揮発性包有物(CAI)とコンドリュールを選別した。
2.選別したCAIとコンドリュールに短寿命核種を用いた年代測定を同位体顕微鏡により行った。
3.色々な隕石毎のCAI,コンドリュール形成時期と形成期間をデータベース化した。
日本学術振興会, 基盤研究(S), 北海道大学, 17104007

Development of Nobel Mass Spectrometer with Ultra-High Sensitivity and Ultra-Trace Sampling for Planetary Exploration
Grants-in-Aid for Scientific Research Grant-in-Aid for Creative Scientific Research
2004 - 2008
ISHIHARA Morio, TOYODA Michisato, UEDA Chiaki, UCHINO Kiichiro, YURIMOTO Hisayoshi, KURAMOTO Kiyoshi, MATSUMOTO Takuya
まず新規に開発する超高感度極微量質量分析システムの構想決定を行い,その検討結果をもとに装置の製作を行った。その後,質量分析部,1次イオン照射系,レーザーイオン化について,それぞれ装置性能評価を行った。
Japan Society for the Promotion of Science, Grant-in-Aid for Creative Scientific Research, Osaka University, 16GS0214

Theoretical and numerical study on Jovian atmospheres:their dynamics, matetialtrensport, and energetics.
Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
2004 - 2007
HAYASHI Yoshi-yuki, WATANABE Shigeto, KURAMOTO Kiyoshi, ISHIWATARI Masaki, ODAKA Masatsugu, NAKAJIMA Kensuke
For the purpose of investigating the interplay among dynamical, thermal, and compositional structures of the atmospheres of Jovian planets, we compiled the current status of corresponding knowledge, developed a hierarchical modeling system, and conducted numerical experiments with those hierardical modeling systems. The main findings of our investigations are summarized as follows:
1. We developed a vertical one-dimensional equilibrium cloud condensation model, which enable us to cover possible atmospheric compositional varieties of the Jovian planets. We found that the contributions to the intensity of stability by the cloud layers associated with the condensation of NH_3 and formation of NH_4SH are not negligible compared with that of H_2O.
2. We developed a two-dimensional cloud convection model incorporating the condensation of NH_3 and H_2O and formation of NH_4SH. We conducted a series of numerical experiments, and found that the H_2O condensation level acts as a distinct dynamical boundary that separates the convective motions above and below it. The stable layers due to NH_3 and NH_4SH clouds cannot suppress the cloudy plumes driven by H_2O condensation healing, resulting in the mixing over the full depth of the atmosphere above the H_2O condensation level.
3. With the application to the Jovian atmosphere in mind, we performed a series of numerical studies on the equatorial acceleration using the three dimensional Bousinesq spherical shell convection model. We found that a strong stable layer in the outer layer helps the development of equatorial retrograde jet. This result may raise a question about the theory where rotating spherical thermal convection explains the cause of the equatorial westerly jets of Jupiter and Saturn.
4. A common software infrastructure, over which those numerical models were constructed, was developed. It contains "gt4f90io" which is a library for I/O of numerical data, and "Rdoc" which is an automatic documentation generator for numerical model codes. We also organized a standard style of Fortran90 programming and constructed a library of Fortran90 functions for basic mathematical manipulations, with which we developed 'Spmodel" which is a set of spectral models. All of the softwares mentioned are open to public on our web site.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), 16204036

大気氷床結合エネルギー収支モデルによる火星気候変動の解明
科学研究費助成事業 若手研究(B)
2004 - 2006
倉本 圭
古火星に想定される高圧の二酸化炭素大気の鉛直一次元大気熱収支・放射対流平衡モデルの開発は,多方向・高波長分解計算の厳密化,ならびに,散乱温室効果をもたらす二酸化炭素氷雲の鉛直プロファイル決定機構の導入を行い,ほぼ満足のできるレベルに到達した.
このモデルを用いて,古火星大気の放射対流平衡構造・熱収支・二酸化氷雲による温室効果についての境界条件を変化させたパラメタスタディを進め,3気圧以上の大気圧と10^5-10^7kg^<-1>の範囲の凝結核混合比があれば,38億年前の火星において全球平均気温がH_2Oの融点を超える温暖な気候が実現されることが分かった.
一方,凝結核混合比が極めて小さい,あるいは大きい場合には,大気圧を増加させてゆくと,やがては地表面へのCO_2凝結が起こり,いわゆる大気崩壊が起こることがわかった.地球大気を参考にすると凝結核混合比は数桁の範囲で変動することが予想される.温室効果の強さが凝結核混合比に強く依存することは,火星の高クレーター密度地域の地形侵食が著しくは進んでいない,つまり温暖湿潤な気候の出現が間欠的であったと示唆されるここと調和する.
大気の地表面への凝結によって形成される二酸化炭素氷床の流動過程について,その数値計算のための流動則と涵養消耗過程についての基礎的な定式化を行った。完成した大気放射モデルから凝結核の挙動が重要なことが判明し,凝結核の移流を考慮した大気-氷床結合モデルが火星の気候変動の理解に有益であることが分かった.
日本学術振興会, 若手研究(B), 北海道大学, Principal investigator, Competitive research funding, 16740263

地球流体力学の知見情報をインターネット上に集積公開して行くための調査研究
科学研究費助成事業 基盤研究(C)
2004 - 2004
林 祥介, 倉本 圭, 小高 正嗣, 石渡 正樹, 竹広 真一, 中島 健介
予備的な国内検討会を実施後,米国への調査旅行を企画し,UNIDATAならびPrinceton大のGFDL/NOAAを訪問,情報技術の進展とそれによる当該分野の教育・研究活動への影響等に関して意見交換を行った.調査の結果を受け,さらに国内検討会を開催し,現在の情勢と当該分野でなされるべき今後の対応について議論を進めた.これらの資料は「地球流体電脳倶楽部」のWEBサーバ上に掲載し公開されており,http://www.gfd-dennou.org/arch/davis/workshop/から適宜たどることができる.
UNIDATAは1983年に設立され,米国の大気科学関連大学連合によって運営される,当該分野の研究教育のための情報基盤を支えるための組織である.データのアーカイブ,必要となるファイル形式の提供(netCDF),データハンドリングと可視化ツールの開発と提供で知られており,また,様々な情報技術開発のコーディネーションを行う.現在,UNIDATAが中心となって,各地に分散しているデータサーバをインターネット上に統合,一つの仮想的なデータベースとして機能せしめ,情報をリアルタイムで提供(OPeNDAP/THREDDS),数値予報モデルと有機的に組み合わし,研究のみならず教育の現場で利用する実験が進められている.残念ながらわが国では気象業務法の縛りがあり,かつ,気象庁が研究教育活動に対してデータを提供する枠組の整備が不十分で,同種の試みを実行することは不可能である.様々な制度がインターネット以前の時代のままであることが問題であり,情報基盤構築をリードするUNIDATAのような組織がないことが状況の改善を困難にしている.
日本学術振興会, 基盤研究(C), 北海道大学, 16634007

GLOBAL DUST CIRCULATION IN THE PROTO-PLANETARY DISK
Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
2001 - 2004
YURIMOTO Hisayoshi, IDA Shigeru, FUJIMOTO Masaki, KURAMOTO Kiyoshi, EMORI Hiroyuki
It is believed that bulk chemical compositions among planets and asteroids in the solar system is similar but slightly different from the solar abundance ratios one another. The variations of the bulk composition may result from a global circulation of dusts around the proto-planetary disk. The dusts spiral into the proto-sun from outer edge of the disk and some of them launched from the inner edge of the disk to the outer-edge. In this study, we made chemical analyses of meteorites and numerical simulations of electro-magnetic effects, dynamic effects and chemical reaction network estimated in the proto-planetary disk. We may conclude the subjects as follows :
1.Oxygen isotopic anomaly observed in the solar system was originated in the parent molecular cloud by a self-shielding effect of carbon monoxides by ultra-violet light irradiation.
2.The oxygen isotopic fractionation in the molecular cloud was separated into interstellar gas and ice phases. Differences of dynamics and chemistry in the disk introduced the anomaly of oxygen isotopes in the solar system.
3.oxygen isotopic compositions of planets were mainly determined by enrichment factor of dusts and evaporation of ice in a proto-planetary disk.
4.A numerical simulation suggests that trajectory around a central star and the mass of gas planets were controlled by gas-dust ratios in a proto-planetary disk. The results correspond to probabilities of extra-solar planets by astronomical observations. This conclusion suggests that amounts of proto-planetary disk are determined by star-formation process, but the planetary formation around the star is controlled by the gas-dust ratio in the disk.
5.Nature of electro-magneto vortex of interstellar plasma was simulated numerically. Inertia effects of electrons are important to the vortex evolution. Larger scale vortex is immediately fractionized to smaller scale ones. This process suggests that material mixing is promptly evolved in the space than ever thought.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), TOKYO INSTITUTE OF TECHNOLOGY, 13304046

対流渦の直接数値計算による惑星CO_2大気の光化学安定性に関する研究
科学研究費助成事業 萌芽研究
2001 - 2003
林 祥介, 小高 正嗣, 倉本 圭, 渡部 重十
今年度はこれまでの火星大気二次元対流計算の延長線上に計算領域の拡張と放射・光化学プロセスの導入を試みた.
計算領域の拡張は,分解脳100mを維持したまま,まず鉛直方向に高度100kmまで拡張することを行い,ついで水平方向にできるだけ広い領域を並列計算技術等を用いて確保することとした.これまでの計算により,対流圏の鉛直対流によって生成される重力波は高度とともにその卓越波数が小さくなることがわかっており,高高度領域での内部重力波による混合の影響を計算するためには同時に水平方向にも十分な計算領域が必要となる.
領域拡張において判明したことは,これまで我々が用いてきた非弾性方程式系の問題点である.非弾性系では音波を含まないため,圧力を求める際には楕円型の微分方程式を解く必要があったが,これは並列化計算における効率を低下させる要素となる.我々は数値コードを再検討した結果,基礎方程式系の見直しを行い新たに音波を考慮した準圧縮方程式系に基づく対流数値モデルの開発を行うことにした.開発中のモデルと関連文書はhttp://www.gfd-dennou.org/arch/deepconv以下に公開している.
放射・光化学プロセスの導入に関しては極めて単純な二酸化炭素の吸収射出ならびに二酸化炭素の光分解過程を組み込み,高高度での物質分布の時間発展を追うことにした.高高度領域を確保するべく水平32kmの狭い領域に限定し,非弾性系モデルを用いた予備的な計算を実行した.残念ながら,二酸化炭素の光分解に対して重力波の砕破混合が働き分解を阻害する傾向を見極めるための十分なパラメタ実験を行うまでには到らなかった.今後準圧縮方程式系によるモデルを用いて計算を継続する予定である.
日本学術振興会, 萌芽研究, 北海道大学, 13874053

Observation of Jovian Visible Aurora and its Generation Mechanism
Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
2000 - 2001
WATANABE Shigeto, TAKAHASHI Yukihiro, KURAMOTO Kiyoshi, HAYASHI Yoshiyuki
We have built an optical observation system of Jovian visible aurora and airglow, which consists of CCD and narrow band filter on ground-based telescope. The emissions have never been measured from ground. We have carried out the observations by use of Rikubetsu 110cm telescope, lidate 60cm telescope and Hokkaido University 10cm telescope from 1999 to 2001. We have also developed an imaging processing system that analyzes the image of Jupiter taken with short exposure time and integrated. We found some emissions in the northern region of Jupiter. Our system may be able to apply to detect very weak signals from planets or airglow.
We have investigated theoretically the atmosphere of Jupiter as well as Venus, Earth and Mars. The results suggested that the interactions with clouds and plasma are important to planetary atmospheres. Especially, at high altitudes the ion-drag effect must be considered in the planetary upper atmospheres.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), HOKKAIDO UNIVERSITY, 12640428

微惑星集積期における火星の熱史と大気形成に関する理論的研究
科学研究費助成事業 奨励研究(A)
1999 - 2000
倉本 圭
集積期の火星熱史について現実的な微惑星サイズ分布を与えた数値シミュレーションを行うと同時に,火星CO_2大気-極冠システムの安定性解析を行った.
熱史の数値シミュレーションから得られた結果は以下の通りである.
1)火星半径が約3000kmに達すると微惑星衝突点の融解が起こり始める.
2)融解開始後,半径がさらに300km成長するまで,サイズの大きな微惑星のみが融解に寄与する.
以上の結果は,火星の大気,マントル,金属核の分化が集積過程の末期に起こり始めることを意味する.
火星において実現し得る大気状態を明らかにするには,大気-極冠システムの安定性の解析が必要である.そのために大気-極冠間の質量交換を考慮した2次元エネルギーバランスモデルを構築した.このモデルは,与えられた日射の緯度分布に対し,大気-地表システムのエネルギー・質量バランスの南北・鉛直構造を解くものである.そこにはCO_2大気の温室効果,緯度間の熱輸送,地表-大気間の熱およびCO_2交換(極冠における凝縮,蒸発)過程が組み込まれている.
このモデルを用いた安定性解析の結果を以下に説明する.大気-極冠システムが長期的な定常状態にあるためには,火星年で積分したCO_2凝結量と蒸発量が釣り合った状態になければならない.それには,大気圧が低く大部分のCO_2が極冠に凝結した"冷たい"定常状態と,極冠が完全に蒸発し大気圧が高い"熱い"定常状態,そしてこれらの中間の状態がありうる.中間状態は不安定であり,仮にこの状態から出発しても数十年で"冷たい"ないしは"熱い"定常状態に遷移する.宇宙空間への大気散逸などによって大気-極冠システムのCO_2量がある臨界量を下回ると,"冷たい"定常状態しか実現されなくなる.この臨界量は大気圧に換算しておよそ0.1-1気圧のオーダーであり,太陽定数,軌道要素,地表のアルベド分布に強く依存する.
日本学術振興会, 奨励研究(A), 北海道大学, Principal investigator, Competitive research funding, 11740117

原始太陽系星雲の物質進化に関する理論的研究
科学研究費助成事業 特別研究員奨励費
1998 - 1998
倉本 圭
日本学術振興会, 特別研究員奨励費, 北海道大学, 97J01245