Article
Astronomy & Astrophysics
Denis Vida, Rhiannon C. Blaauw Erskine, Peter G. Brown, Jonathon Kambulow, Margaret Campbell-Brown, Michael J. Mazur
Summary: Meteor showers and their outbursts pose a significant impact risk to spacecraft, but the lack of global monitoring has hindered accurate observations. This study presents a novel method to compute meteor shower flux using video observations and verifies it against previous data. The flux measurements of several meteor showers are presented, showing variability and differences in peak times.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Martin G. H. Krause, Donna Rodgers-Lee, James E. Dale, Roland Diehl, Chiaki Kobayashi
Summary: Al-26 is an excellent tracer for metal ejection in the Milky Way, providing constraints on supernova feedback modeling. Research suggests a significant fraction of Al-26 exists in the hot component of the Galaxy and diffuses into cold gas for star formation. The branching ratio between hot and cold components is comparable to longer term average results from chemical evolution modeling of galaxies and clusters.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Josep M. Trigo-Rodriguez, Juergen Blum
Summary: Meteor physics provides new insights into cometary disintegration products, bridging various research fields. Estimations of mass distributions of meteoroids from different cometary streams help understand their characteristics.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
M. Asplund, A. M. Amarsi, N. Grevesse
Summary: The chemical composition of the Sun is crucial for astronomy, and researchers have reevaluated the solar abundances of 83 long-lived elements using realistic solar modeling and advanced spectroscopic analysis techniques. The results show agreement with previous studies and provide updated information for future research.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Tristan Mills, P. G. Brown, M. J. Mazur, D. Vida, Peter S. Gural, Althea Moorhead
Summary: In a 4-year survey using Electron Multiplied Charged Coupled Device cameras, 1068 iron meteoroids were identified based on their physical properties. These iron candidates are most abundant in slow-speed meteors, with asteroidal orbits and highly evolved orbits. Future identification techniques using R-band colours could provide a more robust way of identifying fainter iron meteors.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Althea Moorhead, Tiffany Clements, Denis Vida
Summary: This study measured the radiant dispersion of 12 meteor showers using observations from the Global Meteor Network, showing differences in radiant dispersion, Sun-centred ecliptic radiant drift, and shower duration among different meteor showers. The results provide insights into the characteristics and variations of meteor showers in terms of radiant dispersion, Sun-centred ecliptic radiant drift, and shower duration.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
M. D. Campbell-Brown, G. Stober, C. Jacobi, J. Kero, A. Kozlovsky, M. Lester
Summary: The Draconid meteor shower shows irregular strong bursts of activity, with little to no activity in intervening years. Between 1999 and 2018, five outbursts of the Draconid meteor shower were observed using specular meteor radars in Canada and Europe, lasting between 6 and 8 hours, and often not fully visible at a single geographical site. There is at least a twofold difference in peak flux measurements from different radars, with the initial trail radius effect undercorrected for the fragile Draconid meteors.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Yi Li, Guozhu Li, Lianhuan Hu, Xiukuan Zhao, Wenjie Sun, Haiyong Xie, Sipeng Yang, Baiqi Ning
Summary: Observations of four outbursts of the October Draconid meteor shower from 2011 to 2021 using four all-sky interferometric meteor radars in China reveal consistent characteristics such as velocity, duration, and main peak position. A comparison of hourly rates at different years at one location shows variations in peak flux, while the radiants and orbit parameters at different latitudes are generally consistent.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Y. Ellinger, M. Lattelais, F. Pauzat, J-C Guillemin, B. Zanda
Summary: Analysis of organic matter in meteorites shows significant variations in types and abundances of amino acids among different types of carbonaceous chondrites, possibly linked to the conditions during their formation and subsequent alterations.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Y. Kipreos, Margaret Campbell-Brown, P. Brown, D. Vida
Summary: The Daytime Sextantids (DSX) meteor shower is closely related to the Geminids and shares a similar orbit with asteroid 2005 UD. Both optical and radar data suggest that DSX meteors have similar characteristics to Geminids, indicating a common origin.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Yanlin Li, Qihou Zhou, Julio Urbina, Tai-Yin Huang
Summary: This study presents the result of sporadic meteor radiant density distribution using the Arecibo 430 MHz incoherent scatter radar (ISR) for the first time. A numerical orbital simulation algorithm is designed to solve the limitations of the Arecibo radar and obtain key results such as meteoroid density and speed distribution.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
J. Vaubaillon, C. Loir, C. Ciocan, M. Kandeepan, M. Millet, A. Cassagne, L. Lacassagne, P. Da Fonseca, F. Zander, D. Buttsworth, S. Loehle, J. Toth, S. Gray, A. Moingeon, N. Rambaux
Summary: In this study, a meteor cluster consisting of 38 fragments was successfully detected during a meteor shower event on May 31, 2022. The detection was made possible by continuous monitoring and analysis of video data using a computer-vision processing system. The occurrence of such meteor clusters is estimated to be relatively rare, and the probability of self-disruption of meteoroids in interplanetary space is enhanced by low heliocentric distance.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
David Capek, Pavel Koten, Pavel Spurny, Lukas Shrbeny
Summary: This study analyzes the observed data and cluster formation conditions of the September epsilon Perseid (SPE) meteoroid cluster from 2016. The aim is to determine the ejection velocities and age of the cluster members, as well as estimate the most probable formation process. The results suggest that the exfoliation due to thermal stresses is the most likely process of cluster formation.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Lukas Shrbeny, Jiri Borovicka, Pavel Koten, Pavel Spurny, Rostislav Stork, Kamil Hornoch, Vlastimil Vojacek
Summary: The study observed the predicted outburst of the Alpha Monocerotid meteor shower on November 22, 2019 using modernized video and photographic cameras. Only ten meteors were observed, with seven providing velocities, magnitudes, and orbits. The radiants and orbits were found to be similar to the 1995 outburst, and the meteoroids were confirmed to be deficient in sodium. End heights of meteors were all distributed at a constant level of 90 km, unique to this meteor shower.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
P. Koten, D. Capek, P. Spurny, R. Stork, V. Vojacek, J. Bednar
Summary: This study used double-station video observations of the 2006 Geminid meteor shower to investigate the existence of meteor pairs. The results showed a higher than expected number of candidate pairs, but both Monte Carlo simulation and analysis of geometrical positions did not support the presence of real pairs. Instead, all observed cases could be explained as coincidental appearances of unrelated meteors.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Thomas Stephan, Andrew M. Davis
Summary: Molybdenum isotopes in presolar silicon carbide grains and meteorites are influenced by s-process and r-process contributions, with the variations in meteoritic molybdenum isotopes primarily due to s-process enrichments or depletions. By comparing isotopic data, the dichotomy in meteorites can be explained, and a fixed ratio between s-, r-, and p-process contributions is suggested.
ASTROPHYSICAL JOURNAL
(2021)
Article
Geochemistry & Geophysics
Alexander N. Krot, Michail Petaev, Kazuhide Nagashima, Elena Dobrica, Brandon C. Johnson, Melissa D. Cashion
Summary: This study focuses on the mineralogy, petrology, and oxygen isotopic compositions of ferroan olivine-pyroxene-normative cryptocrystalline chondrules (Fe-CCs) in CH chondrites, exploring their origin and the origin of other components in genetically related CH and CB chondrites. The Fe-CCs show two types: compositionally uniform chondrules with euhedral Fe, Ni-metal grains, and metal-free chemically zoned chondrules surrounded by ferroan olivine rims. There is a slight oxygen isotopic difference between Fe-CCs and Mg-CCs, suggesting they formed under different redox conditions in the impact plume.
METEORITICS & PLANETARY SCIENCE
(2022)
Article
Geochemistry & Geophysics
Alexander N. Krot, Patricia M. Doyle, Kazuhide Nagashima, Elena Dobrica, Michail I. Petaev
Summary: The study reports on the mineralogy, petrology, and O-isotope compositions of magnetite and fayalite in metasomatically altered and weakly metamorphosed carbonaceous and unequilibrated ordinary chondrites. The results suggest that fayalite and magnetite in these chondrites may have formed from aqueous fluid-rock interaction on the chondrite parent asteroids, and the observed differences in O-isotope compositions imply spatial and/or temporal variations in water oxygen isotopes in the protoplanetary disk.
METEORITICS & PLANETARY SCIENCE
(2022)
Article
Geochemistry & Geophysics
Joseph Goldstein, Edward R. D. Scott, Timothy B. Winfield, Jijin Yang, Alan Rubin
Summary: By analyzing the cooling rates of various iron meteorites, it was found that different groups of iron meteorites may have experienced cooling processes at different speeds, which may be related to their parent bodies. Additionally, the transformation of the low-Ni phase in taenite was explained based on the observations of cooling rates and different phases present in meteorites with varying cooling rates.
METEORITICS & PLANETARY SCIENCE
(2022)
Article
Geochemistry & Geophysics
Ian S. Sanders, Edward R. D. Scott
Summary: Researchers question the interpretation of isotopic relationship between chondrules and matrix in the Allende chondrite, proposing a hydrothermal alteration model to explain the complementary relationship.
METEORITICS & PLANETARY SCIENCE
(2022)
Article
Astronomy & Astrophysics
Jens Barosch, Larry R. Nittler, Jianhua Wang, Conel M. O'D Alexander, Bradley T. De Gregorio, Cecile Engrand, Yoko Kebukawa, Kazuhide Nagashima, Rhonda M. Stroud, Hikaru Yabuta, Yoshinari Abe, Jerome Aleon, Sachiko Amari, Yuri Amelin, Ken-ichi Bajo, Laure Bejach, Martin Bizzarro, Lydie Bonal, Audrey Bouvier, Richard W. Carlson, Marc Chaussidon, Byeon-Gak Choi, George D. Cody, Emmanuel Dartois, Nicolas Dauphas, Andrew M. Davis, Alexandre Dazzi, Ariane Deniset-Besseau, Tommaso Di Rocco, Jean Duprat, Wataru Fujiya, Ryota Fukai, Ikshu Gautam, Makiko K. Haba, Minako Hashiguchi, Yuki Hibiya, Hiroshi Hidaka, Hisashi Homma, Peter Hoppe, Gary R. Huss, Kiyohiro Ichida, Tsuyoshi Iizuka, Trevor R. Ireland, Akira Ishikawa, Motoo Ito, Shoichi Itoh, Kanami Kamide, Noriyuki Kawasaki, A. L. David Kilcoyne, Noriko T. Kita, Kouki Kitajima, Thorsten Kleine, Shintaro Komatani, Mutsumi Komatsu, Alexander N. Krot, Ming-Chang Liu, Zita Martins, Yuki Masuda, Jeremie Mathurin, Kevin D. McKeegan, Gilles Montagnac, Mayu Morita, Smail Mostefaoui, Kazuko Motomura, Frederic Moynier, Izumi Nakai, Ann N. Nguyen, Takuji Ohigashi, Taiga Okumura, Morihiko Onose, Andreas Pack, Changkun Park, Laurette Piani, Liping Qin, Eric Quirico, Laurent Remusat, Sara S. Russell, Naoya Sakamoto, Scott A. Sandford, Maria Schonbachler, Miho Shigenaka, Hiroki Suga, Lauren Tafla, Yoshio Takahashi, Yasuo Takeichi, Yusuke Tamenori, Haolan Tang, Kentaro Terada, Yasuko Terada, Tomohiro Usui, Maximilien Verdier-Paoletti, Sohei Wada, Meenakshi Wadhwa, Daisuke Wakabayashi, Richard J. Walker, Katsuyuki Yamashita, Shohei Yamashita, Qing-Zhu Yin, Tetsuya Yokoyama, Shigekazu Yoneda, Edward D. Young, Hiroharu Yui, Ai-Cheng Zhang, Masanao Abe, Akiko Miyazaki, Aiko Nakato, Satoru Nakazawa, Masahiro Nishimura, Tatsuaki Okada, Takanao Saiki, Satoshi Tanaka, Fuyuto Terui, Yuichi Tsuda, Sei-ichiro Watanabe, Toru Yada, Kasumi Yogata, Makoto Yoshikawa, Tomoki Nakamura, Hiroshi Naraoka, Takaaki Noguchi, Ryuji Okazaki, Kanako Sakamoto, Shogo Tachibana, Hisayoshi Yurimoto
Summary: Researchers have discovered presolar grains in samples returned from asteroid Ryugu, which have isotopic compositions similar to those found in carbonaceous chondrite meteorites. This finding provides further evidence of the connection between Ryugu and carbonaceous CI chondrites, and also suggests the presence of small-scale heterogeneities in the Ryugu samples.
ASTROPHYSICAL JOURNAL LETTERS
(2022)
Article
Multidisciplinary Sciences
Tetsuya Yokoyama, Kazuhide Nagashima, Izumi Nakai, Edward D. Young, Yoshinari Abe, Jerome Aleon, Conel M. O'D. Alexander, Sachiko Amari, Yuri Amelin, Ken-ichi Bajo, Martin Bizzarro, Audrey Bouvier, Richard W. Carlson, Marc Chaussidon, Byeon-Gak Choi, Nicolas Dauphas, Andrew M. Davis, Tommaso Di Rocco, Wataru Fujiya, Ryota Fukai, Ikshu Gautam, Makiko K. Haba, Yuki Hibiya, Hiroshi Hidaka, Hisashi Homma, Peter Hoppe, Gary R. Huss, Kiyohiro Ichida, Tsuyoshi Iizuka, Trevor R. Ireland, Akira Ishikawa, Motoo Ito, Shoichi Itoh, Noriyuki Kawasaki, Noriko T. Kita, Kouki Kitajima, Thorsten Kleine, Shintaro Komatani, Alexander N. Krot, Ming-Chang Liu, Yuki Masuda, Kevin D. McKeegan, Mayu Morita, Kazuko Motomura, Frederic Moynier, Ann Nguyen, Larry Nittler, Morihiko Onose, Andreas Pack, Changkun Park, Laurette Piani, Liping Qin, Sara S. Russell, Naoya Sakamoto, Maria Schoenbaechler, Lauren Tafla, Haolan Tang, Kentaro Terada, Yasuko Terada, Tomohiro Usui, Sohei Wada, Meenakshi Wadhwa, Richard J. Walker, Katsuyuki Yamashita, Qing-Zhu Yin, Shigekazu Yoneda, Hiroharu Yui, Ai-Cheng Zhang, Harold C. Connolly Jr, Dante S. Lauretta, Tomoki Nakamura, Hiroshi Naraoka, Takaaki Noguchi, Ryuji Okazaki, Kanako Sakamoto, Hikaru Yabuta, Masanao Abe, Masahiko Arakawa, Atsushi Fujii, Masahiko Hayakawa, Naoyuki Hirata, Naru Hirata, Rie Honda, Chikatoshi Honda, Satoshi Hosoda, Yu-ichi Iijima, Hitoshi Ikeda, Masateru Ishiguro, Yoshiaki Ishihara, Takahiro Iwata, Kosuke Kawahara, Shota Kikuchi, Kohei Kitazato, Koji Matsumoto, Moe Matsuoka, Tatsuhiro Michikami, Yuya Mimasu, Akira Miura, Tomokatsu Morota, Satoru Nakazawa, Noriyuki Namiki, Hirotomo Noda, Rina Noguchi, Naoko Ogawa, Kazunori Ogawa, Tatsuaki Okada, Chisato Okamoto, Go Ono, Masanobu Ozaki, Takanao Saiki, Naoya Sakatani, Hirotaka Sawada, Hiroki Senshu, Yuri Shimaki, Kei Shirai, Seiji Sugita, Yuto Takei, Hiroshi Takeuchi, Satoshi Tanaka, Eri Tatsumi, Fuyuto Terui, Yuichi Tsuda, Ryudo Tsukizaki, Koji Wada, Sei-ichiro Watanabe, Manabu Yamada, Tetsuya Yamada, Yukio Yamamoto, Hajime Yano, Yasuhiro Yokota, Keisuke Yoshihara, Makoto Yoshikawa, Kent Yoshikawa, Shizuho Furuya, Kentaro Hatakeda, Tasuku Hayashi, Yuya Hitomi, Kazuya Kumagai, Akiko Miyazaki, Aiko Nakato, Masahiro Nishimura, Hiromichi Soejima, Ayako Suzuki, Toru Yada, Daiki Yamamoto, Kasumi Yogata, Miwa Yoshitake, Shogo Tachibana, Hisayoshi Yurimoto
Summary: Carbonaceous meteorites from C-type asteroids were examined using samples from asteroid (162173) Ryugu. The samples resemble carbonaceous chondrite meteorites, particularly the CI group, and are made up of minerals formed in aqueous fluids. These minerals were altered at a temperature of 37 degrees Celsius about 5.2 million years after the formation of the first solids in the Solar System. The Ryugu samples have a composition similar to the Sun's photosphere.
Article
Geochemistry & Geophysics
Alexander N. Krot, Kazuhide Nagashima, Glenn J. MacPherson, Alexander A. Ulyanov
Summary: The oxygen isotope compositions of CV igneous CAIs indicate that they underwent post-crystallization oxygen isotope exchange due to fluid-rock interaction, but some minerals retained their original compositions. Overall, the oxygen isotope compositions of igneous CAIs are influenced by various factors.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Geochemistry & Geophysics
G. J. MacPherson, K. Nagashima, A. N. Krot, S. M. Kuehner, A. J. Irving, K. Ziegler, L. Mallozzi, C. Corrigan, D. Pitt
Summary: NWA 8418 is a unique chondrite that does not perfectly fit into any existing category. It shows similarities with CV, CK, and CL chondrites, but its abundance of large CAIs and low NiO content align it closest with the CV group. The absence of certain minerals in the alteration products of the CAIs, the magnesium-rich nature of the matrix olivines, and the presence of certain secondary minerals indicate a metamorphic temperature of over 600 degrees C. NWA 8418 is classified as a reduced CV4 chondrite, the first of its kind.
METEORITICS & PLANETARY SCIENCE
(2023)
Article
Multidisciplinary Sciences
Noriyuki Kawasaki, Kazuhide Nagashima, Naoya Sakamoto, Toru Matsumoto, Ken-Ichi Bajo, Sohei Wada, Yohei Igami, Akira Miyake, Takaaki Noguchi, Daiki Yamamoto, Sara S. Russell, Yoshinari Abe, Jerome Aleon, Conel M. O'd Alexander, Sachiko Amari, Yuri Amelin, Martin Bizzarro, Audrey Bouvier, Richard W. Carlson, Marc Chaussidon, Byeon-Gak Choi, Nicolas Dauphas, Andrew M. Davis, Tommaso Di Rocco, Wataru Fujiya, Ryota Fukai, Ikshu Gautam, Makiko K. Haba, Yuki Hibiya, Hiroshi Hidaka, Hisashi Homma, Peter Hoppe, Gary R. Huss, Kiyohiro Ichida, Tsuyoshi Iizuka, Trevor R. Ireland, Akira Ishikawa, Motoo Ito, Shoichi Itoh, Noriko T. Kita, Kouki Kitajima, Thorsten Kleine, Shintaro Komatani, Alexander N. Krot, Ming-Chang Liu, Yuki Masuda, Kevin D. McKeegan, Mayu Morita, Kazuko Motomura, Frederic Moynier, Izumi Nakai, Ann Nguyen, Larry Nittler, Morihiko Onose, Andreas Pack, Changkun Park, Laurette Piani, Liping Qin, Maria Schonbachler, Lauren Tafla, Haolan Tang, Kentaro Terada, Yasuko Terada, Tomohiro Usui, Meenakshi Wadhwa, Richard J. Walker, Katsuyuki Yamashita, Qing-Zhu Yin, Tetsuya Yokoyama, Shigekazu Yoneda, Edward D. Young, Hiroharu Yui, Ai-Cheng Zhang, Tomoki Nakamura, Hiroshi Naraoka, Ryuji Okazaki, Kanako Sakamoto, Hikaru Yabuta, Masanao Abe, Akiko Miyazaki, Aiko Nakato, Masahiro Nishimura, Tatsuaki Okada, Toru Yada, Kasumi Yogata, Satoru Nakazawa, Takanao Saiki, Satoshi Tanaka, Fuyuto Terui, Yuichi Tsuda, Sei-Ichiro Watanabe, Makoto Yoshikawa, Shogo Tachibana, Hisayoshi Yurimoto
Summary: The extraterrestrial materials from asteroid Ryugu and CI chondrites share similar chemical and mineral compositions, suggesting that they both accreted in the outer Solar System closer to the region where comets gather.
Article
Geochemistry & Geophysics
Guy Libourel, Kazuhide Nagashima, Marc Portail, Alexander N. Krot
Summary: Oxygen-isotope studies of carbonaceous chondrite chondrules are crucial for understanding the evolution of the solar protoplanetary disk. Contrary to previous findings, we discovered that the A17O of chondrule olivines from the Yamato 81020 CO3.05 carbonaceous chondrite is independent of their Mg# and fO2. We propose that chondrules record an evolution of an isotopically heterogeneous vapor plume, resulting in the bimodal distribution of Mg-rich olivines.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Geochemistry & Geophysics
David R. Frank, Gary R. Huss, Michael E. Zolensky, Kazuhide Nagashima, Loan Le
Summary: The discovery of a calcium-aluminum-rich inclusion (CAI) in the CI chondrite raises questions about whether CI chondrites are a reliable proxy for the bulk composition of the solar system. Although small amounts of refractory material have been previously identified in CI chondrites, they are not abundant enough to significantly alter the overall composition.
METEORITICS & PLANETARY SCIENCE
(2023)
Article
Geochemistry & Geophysics
Alexander N. Krot, Tasha L. Dunn, Michail I. Petaev, Chi Ma, Kazuhide Nagashima, Jutta Zipfel
Summary: We report on the primary and secondary mineralogies of three types of igneous CAIs from carbonaceous chondrites and compare them with the mineralogy of CAIs from another type of chondrite. We also discuss the nature of the alteration processes that affected these CAIs.
METEORITICS & PLANETARY SCIENCE
(2023)
Article
Geochemistry & Geophysics
Alexander N. Krot, Kazuhide Nagashima, Marina A. Ivanova, Dante Lauretta, Guy Libourel, Brandon C. Johnson, Frank E. Brenker, Viktoria Hoffman, Martin Bizzarro
Summary: The CB metal-rich carbonaceous chondrites are divided into CBa and CBb subgroups. CBa chondrites mainly consist of olivine chondrules and Fe,Ni-metal +/- troilite nodules. CBb chondrites are finer grained and composed of chemically zoned and unzoned Fe,Ni-metal grains, troilite nodules, olivine chondrules, and refractory inclusions. The study of the anomalous metal-rich carbonaceous chondrites Fountain Hills and SG 013 provides important insights into their oxygen isotopic compositions and formation processes.
METEORITICS & PLANETARY SCIENCE
(2023)
Article
Geosciences, Multidisciplinary
Wataru Fujiya, Noriyuki Kawasaki, Kazuhide Nagashima, Naoya Sakamoto, Conel M. O'D. Alexander, Noriko T. Kita, Kouki Kitajima, Yoshinari Abe, Jerome Aleon, Sachiko Amari, Yuri Amelin, Ken-ichi Bajo, Martin Bizzarro, Audrey Bouvier, Richard W. Carlson, Marc Chaussidon, Byeon-Gak Choi, Nicolas Dauphas, Andrew M. Davis, Tommaso Di Rocco, Ryota Fukai, Ikshu Gautam, Makiko K. Haba, Yuki Hibiya, Hiroshi Hidaka, Hisashi Homma, Peter Hoppe, Gary R. Huss, Kiyohiro Ichida, Tsuyoshi Iizuka, Trevor R. Ireland, Akira Ishikawa, Shoichi Itoh, Thorsten Kleine, Shintaro Komatani, Alexander N. Krot, Ming-Chang Liu, Yuki Masuda, Kevin D. McKeegan, Mayu Morita, Kazuko Motomura, Frederic Moynier, Izumi Nakai, Ann Nguyen, Larry Nittler, Morihiko Onose, Andreas Pack, Changkun Park, Laurette Piani, Liping Qin, Sara S. Russell, Maria Schonbachler, Lauren Tafla, Haolan Tang, Kentaro Terada, Yasuko Terada, Tomohiro Usui, Sohei Wada, Meenakshi Wadhwa, Richard J. Walker, Katsuyuki Yamashita, Qing-Zhu Yin, Tetsuya Yokoyama, Shigekazu Yoneda, Edward D. Young, Hiroharu Yui, Ai-Cheng Zhang, Tomoki Nakamura, Hiroshi Naraoka, Takaaki Noguchi, Ryuji Okazaki, Kanako Sakamoto, Hikaru Yabuta, Masanao Abe, Akiko Miyazaki, Aiko Nakato, Masahiro Nishimura, Tatsuaki Okada, Toru Yada, Kasumi Yogata, Satoru Nakazawa, Takanao Saiki, Satoshi Tanaka, Fuyuto Terui, Yuichi Tsuda, Sei-ichiro Watanabe, Makoto Yoshikawa, Shogo Tachibana, Hisayoshi Yurimoto
Summary: The study of samples from asteroid Ryugu brought to Earth by the Hayabusa2 spacecraft revealed that there are variable oxygen and carbon isotopes in the calcium carbonate. This suggests that Ryugu underwent aqueous alteration under different temperature and redox conditions, leading to a unique evolutionary pathway compared to other hydrous meteorites.