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2. Influx of nitrogen-rich material from the outer Solar System indicated by iron nitride in Ryugu samples

Author

Matsumoto, Toru, Noguchi, Takaaki, Miyake, Akira, Igami, Yohei, Haruta, Mitsutaka, Seto, Yusuke, Miyahara, Masaaki, Tomioka, Naotaka, Saito, Hikaru, Hata, Satoshi, Harries, Dennis, Takigawa, Aki, Nakauchi, Yusuke, Tachibana, Shogo, Nakamura, Tomoki, Matsumoto, Megumi, Ishii, Hope A., Bradley, John P., Ohtaki, Kenta, Dobrică, Elena, Leroux, Hugues, Le Guillou, Corentin, Jacob, Damien, de la Peña, Francisco, Laforet, Sylvain, Marinova, Maya, Langenhorst, Falko, Beck, Pierre, Phan, Thi H. V., Rebois, Rolando, Abreu, Neyda M., Gray, Jennifer, Zega, Thomas, Zanetta, Pierre-M., Thompson, Michelle S., Stroud, Rhonda, Burgess, Kate, Cymes, Brittany A., Bridges, John C., Hicks, Leon, Lee, Martin R., Daly, Luke, Bland, Phil A., Zolensky, Michael E., Frank, David R., Martinez, James, Tsuchiyama, Akira, Yasutake, Masahiro, Matsuno, Junya, Okumura, Shota, Mitsukawa, Itaru, Uesugi, Kentaro, Uesugi, Masayuki, Takeuchi, Akihisa, Sun, Mingqi, Enju, Satomi, Michikami, Tatsuhiro, Yurimoto, Hisayoshi, Okazaki, Ryuji, Yabuta, Hikaru, Naraoka, Hiroshi, Sakamoto, Kanako, Yada, Toru, Nishimura, Masahiro, Nakato, Aiko, Miyazaki, Akiko, Yogata, Kasumi, Abe, Masanao, Okada, Tatsuaki, Usui, Tomohiro, Yoshikawa, Makoto, Saiki, Takanao, Tanaka, Satoshi, Terui, Fuyuto, Nakazawa, Satoru, Watanabe, Sei-ichiro, and Tsuda, Yuichi

Published
2024
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3. Mineral Detection of Neutrinos and Dark Matter. A Whitepaper

Author

Baum, Sebastian, Stengel, Patrick, Abe, Natsue, Acevedo, Javier F., Araujo, Gabriela R., Asahara, Yoshihiro, Avignone, Frank, Balogh, Levente, Baudis, Laura, Boukhtouchen, Yilda, Bramante, Joseph, Breur, Pieter Alexander, Caccianiga, Lorenzo, Capozzi, Francesco, Collar, Juan I., Ebadi, Reza, Edwards, Thomas, Eitel, Klaus, Elykov, Alexey, Ewing, Rodney C., Freese, Katherine, Fung, Audrey, Galelli, Claudio, Glasmacher, Ulrich A., Gleason, Arianna, Hasebe, Noriko, Hirose, Shigenobu, Horiuchi, Shunsaku, Hoshino, Yasushi, Huber, Patrick, Ido, Yuki, Igami, Yohei, Ishikawa, Norito, Itow, Yoshitaka, Kamiyama, Takashi, Kato, Takenori, Kavanagh, Bradley J., Kawamura, Yoji, Kazama, Shingo, Kenney, Christopher J., Kilminster, Ben, Kouketsu, Yui, Kozaka, Yukiko, Kurinsky, Noah A., Leybourne, Matthew, Lucas, Thalles, McDonough, William F., Marshall, Mason C., Mateos, Jose Maria, Mathur, Anubhav, Michibayashi, Katsuyoshi, Mkhonto, Sharlotte, Murase, Kohta, Naka, Tatsuhiro, Oguni, Kenji, Rajendran, Surjeet, Sakane, Hitoshi, Sala, Paola, Scholberg, Kate, Semenec, Ingrida, Shiraishi, Takuya, Spitz, Joshua, Sun, Kai, Suzuki, Katsuhiko, Tanin, Erwin H., Vincent, Aaron, Vladimirov, Nikita, Walsworth, Ronald L., and Watanabe, Hiroko

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract

Minerals are solid state nuclear track detectors - nuclear recoils in a mineral leave latent damage to the crystal structure. Depending on the mineral and its temperature, the damage features are retained in the material from minutes (in low-melting point materials such as salts at a few hundred degrees C) to timescales much larger than the 4.5 Gyr-age of the Solar System (in refractory materials at room temperature). The damage features from the $O(50)$ MeV fission fragments left by spontaneous fission of $^{238}$U and other heavy unstable isotopes have long been used for fission track dating of geological samples. Laboratory studies have demonstrated the readout of defects caused by nuclear recoils with energies as small as $O(1)$ keV. This whitepaper discusses a wide range of possible applications of minerals as detectors for $E_R \gtrsim O(1)$ keV nuclear recoils: Using natural minerals, one could use the damage features accumulated over $O(10)$ Myr$-O(1)$ Gyr to measure astrophysical neutrino fluxes (from the Sun, supernovae, or cosmic rays interacting with the atmosphere) as well as search for Dark Matter. Using signals accumulated over months to few-years timescales in laboratory-manufactured minerals, one could measure reactor neutrinos or use them as Dark Matter detectors, potentially with directional sensitivity. Research groups in Europe, Asia, and America have started developing microscopy techniques to read out the $O(1) - O(100)$ nm damage features in crystals left by $O(0.1) - O(100)$ keV nuclear recoils. We report on the status and plans of these programs. The research program towards the realization of such detectors is highly interdisciplinary, combining geoscience, material science, applied and fundamental physics with techniques from quantum information and Artificial Intelligence., Comment: 115 pages, many pictures of tracks. Please see the source file for higher resolution versions of some plots. v2: matches the published version

Published
2023
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4. Oxygen isotopes of anhydrous primary minerals show kinship between asteroid Ryugu and comet 81P/Wild2

Author

Kawasaki, Noriyuki, Nagashima, Kazuhide, Sakamoto, Naoya, Matsumoto, Toru, Bajo, Ken-ichi, Wada, Sohei, Igami, Yohei, Miyake, Akira, Noguchi, Takaaki, Yamamoto, Daiki, Russell, Sara S, Abe, Yoshinari, Aléon, Jérôme, Alexander, Conel M O’D, Amari, Sachiko, Amelin, Yuri, Bizzarro, Martin, Bouvier, Audrey, Carlson, Richard W, Chaussidon, Marc, Choi, Byeon-Gak, Dauphas, Nicolas, Davis, Andrew M, Di Rocco, Tommaso, Fujiya, Wataru, Fukai, Ryota, Gautam, Ikshu, Haba, Makiko K, Hibiya, Yuki, Hidaka, Hiroshi, Homma, Hisashi, Hoppe, Peter, Huss, Gary R, Ichida, Kiyohiro, Iizuka, Tsuyoshi, Ireland, Trevor R, Ishikawa, Akira, Ito, Motoo, Itoh, Shoichi, Kita, Noriko T, Kitajima, Kouki, Kleine, Thorsten, Komatani, Shintaro, Krot, Alexander N, Liu, Ming-Chang, Masuda, Yuki, McKeegan, Kevin D, Morita, Mayu, Motomura, Kazuko, Moynier, Frédéric, Nakai, Izumi, Nguyen, Ann, Nittler, Larry, Onose, Morihiko, Pack, Andreas, Park, Changkun, Piani, Laurette, Qin, Liping, Schönbächler, Maria, Tafla, Lauren, Tang, Haolan, Terada, Kentaro, Terada, Yasuko, Usui, Tomohiro, Wadhwa, Meenakshi, Walker, Richard J, Yamashita, Katsuyuki, Yin, Qing-Zhu, Yokoyama, Tetsuya, Yoneda, Shigekazu, Young, Edward D, Yui, Hiroharu, Zhang, Ai-Cheng, Nakamura, Tomoki, Naraoka, Hiroshi, Okazaki, Ryuji, Sakamoto, Kanako, Yabuta, Hikaru, Abe, Masanao, Miyazaki, Akiko, Nakato, Aiko, Nishimura, Masahiro, Okada, Tatsuaki, Yada, Toru, Yogata, Kasumi, Nakazawa, Satoru, Saiki, Takanao, Tanaka, Satoshi, Terui, Fuyuto, Tsuda, Yuichi, Watanabe, Sei-ichiro, Yoshikawa, Makoto, Tachibana, Shogo, and Yurimoto, Hisayoshi

Subjects
Earth Sciences, Physical Sciences, Space Sciences, Geology, Prevention
Abstract

The extraterrestrial materials returned from asteroid (162173) Ryugu consist predominantly of low-temperature aqueously formed secondary minerals and are chemically and mineralogically similar to CI (Ivuna-type) carbonaceous chondrites. Here, we show that high-temperature anhydrous primary minerals in Ryugu and CI chondrites exhibit a bimodal distribution of oxygen isotopic compositions: 16O-rich (associated with refractory inclusions) and 16O-poor (associated with chondrules). Both the 16O-rich and 16O-poor minerals probably formed in the inner solar protoplanetary disk and were subsequently transported outward. The abundance ratios of the 16O-rich to 16O-poor minerals in Ryugu and CI chondrites are higher than in other carbonaceous chondrite groups but are similar to that of comet 81P/Wild2, suggesting that Ryugu and CI chondrites accreted in the outer Solar System closer to the accretion region of comets.

Published
2022

5. A history of mild shocks experienced by the regolith particles on hydrated asteroid Ryugu

Author

Tomioka, Naotaka, Yamaguchi, Akira, Ito, Motoo, Uesugi, Masayuki, Imae, Naoya, Shirai, Naoki, Ohigashi, Takuji, Kimura, Makoto, Liu, Ming-Chang, Greenwood, Richard C., Uesugi, Kentaro, Nakato, Aiko, Yogata, Kasumi, Yuzawa, Hayato, Kodama, Yu, Hirahara, Kaori, Sakurai, Ikuya, Okada, Ikuo, Karouji, Yuzuru, Okazaki, Keishi, Kurosawa, Kosuke, Noguchi, Takaaki, Miyake, Akira, Miyahara, Masaaki, Seto, Yusuke, Matsumoto, Toru, Igami, Yohei, Nakazawa, Satoru, Okada, Tatsuaki, Saiki, Takanao, Tanaka, Satoshi, Terui, Fuyuto, Yoshikawa, Makoto, Miyazaki, Akiko, Nishimura, Masahiro, Yada, Toru, Abe, Masanao, Usui, Tomohiro, Watanabe, Sei-ichiro, and Tsuda, Yuichi

Published
2023
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6. A dehydrated space-weathered skin cloaking the hydrated interior of Ryugu

Author

Noguchi, Takaaki, Matsumoto, Toru, Miyake, Akira, Igami, Yohei, Haruta, Mitsutaka, Saito, Hikaru, Hata, Satoshi, Seto, Yusuke, Miyahara, Masaaki, Tomioka, Naotaka, Ishii, Hope A., Bradley, John P., Ohtaki, Kenta K., Dobrică, Elena, Leroux, Hugues, Le Guillou, Corentin, Jacob, Damien, de la Peña, Francisco, Laforet, Sylvain, Marinova, Maya, Langenhorst, Falko, Harries, Dennis, Beck, Pierre, Phan, Thi H. V., Rebois, Rolando, Abreu, Neyda M., Gray, Jennifer, Zega, Thomas, Zanetta, Pierre-M., Thompson, Michelle S., Stroud, Rhonda, Burgess, Kate, Cymes, Brittany A., Bridges, John C., Hicks, Leon, Lee, Martin R., Daly, Luke, Bland, Phil A., Zolensky, Michael E., Frank, David R., Martinez, James, Tsuchiyama, Akira, Yasutake, Masahiro, Matsuno, Junya, Okumura, Shota, Mitsukawa, Itaru, Uesugi, Kentaro, Uesugi, Masayuki, Takeuchi, Akihisa, Sun, Mingqi, Enju, Satomi, Takigawa, Aki, Michikami, Tatsuhiro, Nakamura, Tomoki, Matsumoto, Megumi, Nakauchi, Yusuke, Abe, Masanao, Arakawa, Masahiko, Fujii, Atsushi, Hayakawa, Masahiko, Hirata, Naru, Hirata, Naoyuki, Honda, Rie, Honda, Chikatoshi, Hosoda, Satoshi, Iijima, Yu-ichi, Ikeda, Hitoshi, Ishiguro, Masateru, Ishihara, Yoshiaki, Iwata, Takahiro, Kawahara, Kousuke, Kikuchi, Shota, Kitazato, Kohei, Matsumoto, Koji, Matsuoka, Moe, Mimasu, Yuya, Miura, Akira, Morota, Tomokatsu, Nakazawa, Satoru, Namiki, Noriyuki, Noda, Hirotomo, Noguchi, Rina, Ogawa, Naoko, Ogawa, Kazunori, Okada, Tatsuaki, Okamoto, Chisato, Ono, Go, Ozaki, Masanobu, Saiki, Takanao, Sakatani, Naoya, Sawada, Hirotaka, Senshu, Hiroki, Shimaki, Yuri, Shirai, Kei, Sugita, Seiji, Takei, Yuto, Takeuchi, Hiroshi, Tanaka, Satoshi, Tatsumi, Eri, Terui, Fuyuto, Tsukizaki, Ryudo, Wada, Koji, Yamada, Manabu, Yamada, Tetsuya, Yamamoto, Yukio, Yano, Hajime, Yokota, Yasuhiro, Yoshihara, Keisuke, Yoshikawa, Makoto, Yoshikawa, Kent, Fukai, Ryohta, Furuya, Shizuho, Hatakeda, Kentaro, Hayashi, Tasuku, Hitomi, Yuya, Kumagai, Kazuya, Miyazaki, Akiko, Nakato, Aiko, Nishimura, Masahiro, Soejima, Hiromichi, Suzuki, Ayako I., Usui, Tomohiro, Yada, Toru, Yamamoto, Daiki, Yogata, Kasumi, Yoshitake, Miwa, Connolly, Jr, Harold C., Lauretta, Dante S., Yurimoto, Hisayoshi, Nagashima, Kazuhide, Kawasaki, Noriyuki, Sakamoto, Naoya, Okazaki, Ryuji, Yabuta, Hikaru, Naraoka, Hiroshi, Sakamoto, Kanako, Tachibana, Shogo, Watanabe, Sei-ichiro, and Tsuda, Yuichi

Published
2023
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7. Complex mixture of organic matter in a xenolithic clast from the Zag meteorite revealed by coordinated analyses using AFM-IR, NanoSIMS and STXM/XANES

Author

Kebukawa, Yoko, Mathurin, Jérémie, Dartois, Emmanuel, Dazzi, Alexandre, Deniset-Besseau, Ariane, Duprat, Jean, Remusat, Laurent, Noguchi, Takaaki, Miyake, Akira, Igami, Yohei, Paoletti, Maximilien Verdier, Zolensky, Michael E., Engrand, Cécile, Sandt, Christophe, Borondics, Ferenc, Yamashita, Shohei, Wakabayashi, Daisuke, Takeichi, Yasuo, and Takahashi, Yoshio

Published
2023
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8. Nonequilibrium spherulitic magnetite in the Ryugu samples

Author

Dobrică, Elena, Ishii, Hope A., Bradley, John P., Ohtaki, Kenta, Brearley, Adrian J., Noguchi, Takaaki, Matsumoto, Toru, Miyake, Akira, Igami, Yohei, Haruta, Mitsutaka, Saito, Hikaru, Hata, Satoshi, Seto, Yusuke, Miyahara, Masaaki, Tomioka, Naotaka, Leroux, Hugues, Le Guillou, Corentin, Jacob, Damien, de la Peña, Francisco, Laforet, Sylvain, Marinova, Maya, Langenhorst, Falko, Harries, Dennis, Beck, Pierre, Phan, Thi H.V., Rebois, Rolando, Abreu, Neyda M., Gray, Jennifer, Zega, Thomas, Zanetta, Pierre-M., Thompson, Michelle S., Stroud, Rhonda, Burgess, Kate, Cymes, Brittany A., Bridges, John C., Hicks, Leon, Lee, Martin R., Daly, Luke, Bland, Phil A., Zolensky, Michael E., Frank, David R., Martinez, James, Tsuchiyama, Akira, Yasutake, Masahiro, Matsuno, Junya, Okumura, Shota, Mitsukawa, Itaru, Uesugi, Kentaro, Uesugi, Masayuki, Takeuchi, Akihisa, Sun, Mingqi, Enju, Satomi, Takigawa, Aki, Michikami, Tatsuhiro, Nakamura, Tomoki, Matsumoto, Megumi, Nakauchi, Yusuke, Yurimoto, Hisayoshi, Okazaki, Ryuji, Yabuta, Hikaru, Naraoka, Hiroshi, Sakamoto, Kanako, Tachibana, Shogo, Yada, Toru, Nishimura, Masahiro, Nakato, Aiko, Miyazaki, Akiko, Yogata, Kasumi, Abe, Masanao, Okada, Tatsuaki, Usui, Tomohiro, Yoshikawa, Makoto, Saiki, Takanao, Tanaka, Satoshi, Terui, Fuyuto, Nakazawa, Satoru, Watanabe, Sei-ichiro, and Tsuda, Yuichi

Published
2023
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9. Incipient space weathering on asteroid 162173 Ryugu recorded by pyrrhotite

Author

Harries, Dennis, primary, Matsumoto, Toru, additional, Langenhorst, Falko, additional, Noguchi, Takaaki, additional, Miyake, Akira, additional, Igami, Yohei, additional, Haruta, Mitsutaka, additional, Seto, Yusuke, additional, Miyahara, Masaaki, additional, Tomioka, Naotaka, additional, Saito, Hikaru, additional, Hata, Satoshi, additional, Takigawa, Aki, additional, Nakauchi, Yusuke, additional, Tachibana, Shogo, additional, Nakamura, Tomoki, additional, Matsumoto, Megumi, additional, Ishii, Hope A., additional, Bradley, John P., additional, Ohtaki, Kenta, additional, Dobrică, Elena, additional, Leroux, Hugues, additional, Le Guillou, Corentin, additional, Jacob, Damien, additional, de la Peña, Francisco, additional, Laforet, Sylvain, additional, Mouloud, Bahae‐eddine, additional, Marinova, Maya, additional, Beck, Pierre, additional, Phan, Van T. H., additional, Rebois, Rolando, additional, Abreu, Neyda M., additional, Gray, Jennifer, additional, Zega, Thomas, additional, Zanetta, Pierre‐M., additional, Thompson, Michelle S., additional, Stroud, Rhonda, additional, Burgess, Kate, additional, Cymes, Brittany A., additional, Bridges, John C., additional, Hicks, Leon, additional, Lee, Martin R., additional, Daly, Luke, additional, Bland, Phil A., additional, Zolensky, Michael E., additional, Frank, David R., additional, Martinez, James, additional, Tsuchiyama, Akira, additional, Yasutake, Masahiro, additional, Matsuno, Junya, additional, Okumura, Shota, additional, Mitsukawa, Itaru, additional, Uesugi, Kentaro, additional, Uesugi, Masayuki, additional, Takeuchi, Akihisa, additional, Sun, Mingqi, additional, Enju, Satomi, additional, Michikami, Tatsuhiro, additional, Yurimoto, Hisayoshi, additional, Okazaki, Ryuji, additional, Yabuta, Hikaru, additional, Naraoka, Hiroshi, additional, Sakamoto, Kanako, additional, Yada, Toru, additional, Nishimura, Masahiro, additional, Nakato, Aiko, additional, Miyazaki, Akiko, additional, Yogata, Kasumi, additional, Abe, Masanao, additional, Okada, Tatsuaki, additional, Usui, Tomohiro, additional, Yoshikawa, Makoto, additional, Saiki, Takanao, additional, Tanaka, Satoshi, additional, Terui, Fuyuto, additional, Nakazawa, Satoru, additional, Watanabe, Sei‐ichiro, additional, and Tsuda, Yuichi, additional

Published
2024
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10. Four‐dimensional‐STEM analysis of the phyllosilicate‐rich matrix of Ryugu samples.

Author

Mouloud, Bahae‐eddine, Jacob, Damien, de la Peña, Francisco, Marinova, Maya, Le Guillou, Corentin, Viennet, Jean‐Christophe, Laforet, Sylvain, Leroux, Hugues, Teurtrie, Adrien, Noguchi, Takaaki, Matsumoto, Toru, Miyake, Akira, Igami, Yohei, Haruta, Mitsutaka, Saito, Hikaru, Hata, Satoshi, Seto, Yusuke, Miyahara, Masaaki, Tomioka, Naotaka, and Ishii, Hope A.

Subjects
SCANNING transmission electron microscopy, PYRRHOTITE, SMECTITE, MINERALOGY, ORGANIC compounds
Abstract

Ryugu asteroid grains brought back to the Earth by the Hayabusa2 space mission are pristine samples containing hydrated minerals and organic compounds. Here, we investigate the mineralogy of their phyllosilicate‐rich matrix with four‐dimensional scanning transmission electron microscopy (4D‐STEM). We have identified and mapped the mineral phases at the nanometer scale (serpentine, smectite, pyrrhotite), observed the presence of Ni‐bearing pyrrhotite, and identified the serpentine polymorph as lizardite, in agreement with the reported aqueous alteration history of Ryugu. Furthermore, we have mapped the d‐spacings of smectite and observed a broad distribution of values, ranging from 1 to 2 nm, with an average d‐spacing of 1.24 nm, indicating significant heterogeneity within the sample. Such d‐spacing variability could be the result of either the presence of organic matter trapped in the interlayers or the influence of various geochemical conditions at the submicrometer scale, suggestive of a range of organic compounds and/or changes in smectite crystal chemistry. [ABSTRACT FROM AUTHOR]

Published
2024
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11. In situ investigation of an organic micro‐globule and its mineralogical context within a Ryugu "sand" grain.

Author

Phan, Van T. H., Beck, Pierre, Rebois, Rolando, Quirico, Eric, Noguchi, Takaaki, Matsumoto, Toru, Miyake, Akira, Igami, Yohei, Haruta, Mitsutaka, Saito, Hikaru, Hata, Satoshi, Seto, Yusuke, Miyahara, Masaaki, Tomioka, Naotaka, Ishii, Hope A., Bradley, John P., Ohtaki, Kenta K., Dobrică, Elena, Leroux, Hugues, and Le Guillou, Corentin

Subjects
FOURIER transform infrared spectroscopy, INTERSTELLAR medium, ATMOSPHERE, CHONDRITES, INVESTIGATION reports, ASTEROIDS
Abstract

The Hayabusa2 mission from the Japan Aerospace Exploration Agency (JAXA) returned to the Earth samples of carbonaceous asteroid (162173) Ryugu. This mission offers a unique opportunity to investigate in the laboratory samples from a C‐type asteroid, without physical or chemical alteration by the terrestrial atmosphere. Here, we report on an investigation of the mineralogy and the organo‐chemistry of Hayabusa2 samples using a combination of micro‐ and nano‐infrared spectroscopy. Particles investigated with conventional FTIR spectroscopy have spectra dominated by phyllosilicate‐related absorption, as observed for samples of CI‐chondrites, selected ungrouped carbonaceous chondrites, and selected hydrated micrometeorites. Ryugu samples show smaller sulfate‐related absorption than CI‐chondrites. Our samples that were only briefly exposed to the Earth atmosphere show absorptions related to molecular water, revealing fast terrestrial contamination of the spectral signature at 3 μm. Overall, our FTIR data are in agreement with other work done on Ryugu samples, revealing a low degree of mineralogical variability across Ryugu samples. AFM‐IR mapping of the grains shows the presence of a micrometer‐sized organic globule in one of our analyzed grains. The AFM‐IR spectra obtained on this globule are similar to IR spectra obtained on IOM suggesting that it is constituted of refractory organic matter. This globule may host silicate in its interior, with a different mineralogy than bulk Ryugu phyllosilicate. The shape, presence of peculiar silicate, and the nature of organic constituting the globule point toward a pre‐accretionary origin of this globule and that at least part of Ryugu organics were inherited from the protosolar nebulae or the interstellar media. Altogether, our results show the similarities between Ryugu samples and CI chondrites. [ABSTRACT FROM AUTHOR]

Published
2024
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12. Phyllosilicates with embedded Fe‐based nanophases in Ryugu and Orgueil.

Author

Leroux, Hugues, Le Guillou, Corentin, Marinova, Maya, Laforet, Sylvain, Viennet, Jean‐Christophe, Mouloud, Bahae‐Eddine, Teurtrie, Adrien, de la Peña, Francisco, Jacob, Damien, Hallatt, Daniel, Fernandez, Mario Pelaez, Troadec, David, Noguchi, Takaaki, Matsumoto, Toru, Miyake, Akira, Igami, Yohei, Haruta, Mitsutaka, Saito, Hikaru, Hata, Satoshi, and Seto, Yusuke

Subjects
SCANNING transmission electron microscopy, SAPONITE, PHYLLOSILICATES, METAL sulfides, PETROLOGY, CARBONACEOUS aerosols
Abstract

Samples were recently collected from the carbonaceous asteroid (162173) Ryugu, by the Japan Aerospace Exploration Agency (JAXA) Hayabusa2 mission. They resemble CI chondrites material, thus showing clear evidence of extensive aqueous alteration attested by the widespread presence of a mixture of serpentine and saponite. We present here a scanning transmission electron microscopy study of the Ryugu dominant lithology of the phyllosilicate matrix at the nanometer scale, which we compare with that of the Orgueil CI chondrite. In both objects, the phyllosilicates are of comparable nature and texture, consisting of a mixture of small‐sized crystallites of serpentine and saponite. At the micrometer scale or less, the texture is an alternation of fine and coarse domains. The fine‐grained regions are dominated by saponite. In Ryugu, they enclose numerous Fe,Ni nanosulfides, whereas in Orgueil, S‐ and Ni‐rich ferrihydrite is abundant. The coarse‐grained regions contain more serpentine and no or little Fe,Ni sulfides or ferrihydrite. Scanning transmission x‐ray microscopy at the Fe‐L3 edge also reveals that iron valency of phyllosilicates is higher and more homogeneous in Orgueil (~70% Fe3+) than in Ryugu (<50% Fe3+). We interpret the observed textures as being mostly a consequence of aqueous alteration, likely resulting from the replacement by phyllosilicates of submicrometric components, initially agglomerated by a primary accretion. The fine‐grained domains may result from the replacement of GEMS (GEMS—glass with embedded metal and sulfides) objects or from other types of nanometric assemblages of silicate and Fe‐based nanophases. On the other hand, the coarse‐grained regions may correspond to the replacement of anhydrous crystalline silicates of the olivine and pyroxene type. The major difference is the presence of Fe,Ni sulfides in Ryugu and of ferrihydrite and higher iron valency of phyllosilicates in Orgueil. This might be due to long‐term terrestrial weathering that would have destabilized the nanosulfides. We also explore an alternative scenario involving more oxidizing hydrothermal conditions on the Orgueil parent body. [ABSTRACT FROM AUTHOR]

Published
2024
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13. Mineralogy and petrology of fine‐grained samples recovered from the asteroid (162173) Ryugu.

Author

Noguchi, Takaaki, Matsumoto, Toru, Miyake, Akira, Igami, Yohei, Haruta, Mitsutaka, Saito, Hikaru, Hata, Satoshi, Seto, Yusuke, Miyahara, Masaaki, Tomioka, Naotaka, Ishii, Hope A., Bradley, John P., Ohtaki, Kenta K., Dobrică, Elena, Leroux, Hugues, Guillou, Corentin Le, Jacob, Damien, de la Peña, Francisco, Laforet, Sylvain, and Mouloud, Bahae‐Eddine

Subjects
SCANNING electron microscopes, SAPONITE, SPACE environment, MAGNESITE, MINERALOGY
Abstract

Samples returned from the carbonaceous asteroid (162173) Ryugu by the Hayabusa2 mission revealed that Ryugu is composed of materials consistent with CI chondrites and some types of space weathering. We report detailed mineralogy of the fine‐grained Ryugu samples allocated to our "Sand" team and report additional space weathering features found on the grains. The dominant mineralogy is composed of a fine‐grained mixture of Mg‐rich saponite and serpentine, magnetite, pyrrhotite, pentlandite, dolomite, and Fe‐bearing magnesite. These grains have mineralogy comparable to that of CI chondrites, showing severe aqueous alteration but lacking ferrihydrite and sulfate. These results are similar to previous works on large Ryugu grains. In addition to the major minerals, we also find many minerals that are rare or have not been reported among CI chondrites. Accessory minerals identified are hydroxyapatite, Mg‐Na phosphate, olivine, low‐Ca pyroxene, Mg‐Al spinel, chromite, manganochromite, eskolaite, ilmenite, cubanite, polydymite, transjordanite, schreibersite, calcite, moissanite, and poorly crystalline phyllosilicate. We also show scanning transmission electron microscope and scanning electron microscope compositional maps and images of some space‐weathered grains and severely heated and melted grains. Although our mineralogical results are consistent with that of millimeter‐sized grains, the fine‐grained fraction is best suited to investigate impact‐induced space weathering. [ABSTRACT FROM AUTHOR]

Published
2024
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16. Microstructural and chemical features of impact melts on Ryugu particle surfaces: Records of interplanetary dust hit on asteroid Ryugu

Author

Matsumoto, Megumi, primary, Matsuno, Junya, additional, Tsuchiyama, Akira, additional, Nakamura, Tomoki, additional, Enokido, Yuma, additional, Kikuiri, Mizuha, additional, Nakato, Aiko, additional, Yasutake, Masahiro, additional, Uesugi, Kentaro, additional, Takeuchi, Akihisa, additional, Enju, Satomi, additional, Okumura, Shota, additional, Mitsukawa, Itaru, additional, Sun, Mingqi, additional, Miyake, Akira, additional, Haruta, Mitsutaka, additional, Igami, Yohei, additional, Yurimoto, Hisayoshi, additional, Noguchi, Takaaki, additional, Okazaki, Ryuji, additional, Yabuta, Hikaru, additional, Naraoka, Hiroshi, additional, Sakamoto, Kanako, additional, Tachibana, Shogo, additional, Zolensky, Michael, additional, Yada, Toru, additional, Nishimura, Masahiro, additional, Miyazaki, Akiko, additional, Yogata, Kasumi, additional, Abe, Masanao, additional, Okada, Tatsuaki, additional, Usui, Tomohiro, additional, Yoshikawa, Makoto, additional, Saiki, Takanao, additional, Tanaka, Satoshi, additional, Terui, Fuyuto, additional, Nakazawa, Satoru, additional, Watanabe, Sei-ichiro, additional, and Tsuda, Yuichi, additional

Published
2024
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17. Mineralogy and petrology of fine‐grained samples recovered from the asteroid (162173) Ryugu

Author

Noguchi, Takaaki, primary, Matsumoto, Toru, additional, Miyake, Akira, additional, Igami, Yohei, additional, Haruta, Mitsutaka, additional, Saito, Hikaru, additional, Hata, Satoshi, additional, Seto, Yusuke, additional, Miyahara, Masaaki, additional, Tomioka, Naotaka, additional, Ishii, Hope A., additional, Bradley, John P., additional, Ohtaki, Kenta K., additional, Dobrică, Elena, additional, Leroux, Hugues, additional, Guillou, Corentin Le, additional, Jacob, Damien, additional, de la Peña, Francisco, additional, Laforet, Sylvain, additional, Mouloud, Bahae‐Eddine, additional, Marinova, Maya, additional, Langenhorst, Falko, additional, Harries, Dennis, additional, Beck, Pierre, additional, Phan, Thi H. V., additional, Rebois, Rolando, additional, Abreu, Neyda M., additional, Gray, Jennifer, additional, Zega, Thomas, additional, Zanetta, Pierre‐M., additional, Thompson, Michelle S., additional, Stroud, Rhonda, additional, Burgess, Kate, additional, Cymes, Brittany A., additional, Bridges, John C., additional, Hicks, Leon, additional, Lee, Martin R., additional, Daly, Luke, additional, Bland, Phil A., additional, Smith, William A., additional, McFadzean, Sam, additional, Martin, Pierre‐Etienne, additional, Bagot, Paul A. J., additional, Fougerouse, Dennis, additional, Saxey, David W., additional, Reddy, Steven, additional, Rickard, William D. A., additional, Zolensky, Michael E., additional, Frank, David R., additional, Martinez, James, additional, Tsuchiyama, Akira, additional, Yasutake, Masahiro, additional, Matsuno, Junya, additional, Okumura, Shota, additional, Mitsukawa, Itaru, additional, Uesugi, Kentaro, additional, Uesugi, Masayuki, additional, Takeuchi, Akihisa, additional, Sun, Mingqi, additional, Enju, Satomi, additional, Takigawa, Aki, additional, Michikami, Tatsuhiro, additional, Nakamura, Tomoki, additional, Matsumoto, Megumi, additional, Nakauchi, Yusuke, additional, Abe, Masanao, additional, Nakazawa, Satoru, additional, Okada, Tatsuaki, additional, Saiki, Takanao, additional, Tanaka, Satoshi, additional, Terui, Fuyuto, additional, Yoshikawa, Makoto, additional, Miyazaki, Akiko, additional, Nakato, Aiko, additional, Nishimura, Masahiro, additional, Usui, Tomohiro, additional, Yada, Toru, additional, Yurimoto, Hisayoshi, additional, Nagashima, Kazuhide, additional, Kawasaki, Noriyuki, additional, Sakamotoa, Naoya, additional, Hoppe, Peter, additional, Okazaki, Ryuji, additional, Yabuta, Hikaru, additional, Naraoka, Hiroshi, additional, Sakamoto, Kanako, additional, Tachibana, Shogo, additional, Watanabe, Sei‐ichiro, additional, and Tsuda, Yuichi, additional

Published
2023
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18. Phyllosilicates with embedded Fe‐based nanophases in Ryugu and Orgueil

Author

Leroux, Hugues, primary, Le Guillou, Corentin, additional, Marinova, Maya, additional, Laforet, Sylvain, additional, Viennet, Jean‐Christophe, additional, Mouloud, Bahae‐Eddine, additional, Teurtrie, Adrien, additional, de la Peña, Francisco, additional, Jacob, Damien, additional, Hallatt, Daniel, additional, Fernandez, Mario Pelaez, additional, Troadec, David, additional, Noguchi, Takaaki, additional, Matsumoto, Toru, additional, Miyake, Akira, additional, Igami, Yohei, additional, Haruta, Mitsutaka, additional, Saito, Hikaru, additional, Hata, Satoshi, additional, Seto, Yusuke, additional, Miyahara, Masaaki, additional, Tomioka, Naotaka, additional, Ishii, Hope A., additional, Bradley, John P., additional, Ohtaki, Kenta K., additional, Dobrică, Elena, additional, Langenhorst, Falko, additional, Harries, Dennis, additional, Beck, Pierre, additional, Phan, Thi H. V., additional, Rebois, Rolando, additional, Abreu, Neyda M., additional, Gray, Jennifer, additional, Zega, Thomas, additional, Zanetta, Pierre‐M., additional, Thompson, Michelle S., additional, Stroud, Rhonda, additional, Burgess, Kate, additional, Cymes, Brittany A., additional, Bridges, John C., additional, Hicks, Leon, additional, Lee, Martin R., additional, Daly, Luke, additional, Bland, Phil A., additional, Zolensky, Michael E., additional, Frank, David R., additional, Martinez, James, additional, Tsuchiyama, Akira, additional, Yasutake, Masahiro, additional, Matsuno, Junya, additional, Okumura, Shota, additional, Mitsukawa, Itaru, additional, Uesugi, Kentaro, additional, Uesugi, Masayuki, additional, Takeuchi, Akihisa, additional, Sun, Mingqi, additional, Enju, Satomi, additional, Takigawa, Aki, additional, Michikami, Tatsuhiro, additional, Nakamura, Tomoki, additional, Matsumoto, Megumi, additional, Nakauchi, Yusuke, additional, Abe, Masanao, additional, Nakazawa, Satoru, additional, Okada, Tatsuaki, additional, Saiki, Takanao, additional, Tanaka, Satoshi, additional, Terui, Fuyuto, additional, Yoshikawa, Makoto, additional, Miyazaki, Akiko, additional, Nakato, Aiko, additional, Nishimura, Masahiro, additional, Usui, Tomohiro, additional, Yada, Toru, additional, Yurimoto, Hisayoshi, additional, Nagashima, Kazuhide, additional, Kawasaki, Noriyuki, additional, Sakamotoa, Naoya, additional, Okazaki, Ryuji, additional, Yabuta, Hikaru, additional, Naraoka, Hiroshi, additional, Sakamoto, Kanako, additional, Tachibana, Shogo, additional, Watanabe, Sei‐Ichiro, additional, and Tsuda, Yuichi, additional

Published
2023
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20. Mineral detection of neutrinos and dark matter. A whitepaper

Author

Baum, Sebastian, primary, Stengel, Patrick, additional, Abe, Natsue, additional, Acevedo, Javier F., additional, Araujo, Gabriela R., additional, Asahara, Yoshihiro, additional, Avignone, Frank, additional, Balogh, Levente, additional, Baudis, Laura, additional, Boukhtouchen, Yilda, additional, Bramante, Joseph, additional, Breur, Pieter Alexander, additional, Caccianiga, Lorenzo, additional, Capozzi, Francesco, additional, Collar, Juan I., additional, Ebadi, Reza, additional, Edwards, Thomas, additional, Eitel, Klaus, additional, Elykov, Alexey, additional, Ewing, Rodney C., additional, Freese, Katherine, additional, Fung, Audrey, additional, Galelli, Claudio, additional, Glasmacher, Ulrich A., additional, Gleason, Arianna, additional, Hasebe, Noriko, additional, Hirose, Shigenobu, additional, Horiuchi, Shunsaku, additional, Hoshino, Yasushi, additional, Huber, Patrick, additional, Ido, Yuki, additional, Igami, Yohei, additional, Ishikawa, Norito, additional, Itow, Yoshitaka, additional, Kamiyama, Takashi, additional, Kato, Takenori, additional, Kavanagh, Bradley J., additional, Kawamura, Yoji, additional, Kazama, Shingo, additional, Kenney, Christopher J., additional, Kilminster, Ben, additional, Kouketsu, Yui, additional, Kozaka, Yukiko, additional, Kurinsky, Noah A., additional, Leybourne, Matthew, additional, Lucas, Thalles, additional, McDonough, William F., additional, Marshall, Mason C., additional, Mateos, Jose Maria, additional, Mathur, Anubhav, additional, Michibayashi, Katsuyoshi, additional, Mkhonto, Sharlotte, additional, Murase, Kohta, additional, Naka, Tatsuhiro, additional, Oguni, Kenji, additional, Rajendran, Surjeet, additional, Sakane, Hitoshi, additional, Sala, Paola, additional, Scholberg, Kate, additional, Semenec, Ingrida, additional, Shiraishi, Takuya, additional, Spitz, Joshua, additional, Sun, Kai, additional, Suzuki, Katsuhiko, additional, Tanin, Erwin H., additional, Vincent, Aaron, additional, Vladimirov, Nikita, additional, Walsworth, Ronald L., additional, and Watanabe, Hiroko, additional

Published
2023
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22. Re-distribution of volatiles on the airless surface of the C-type carbonaceous asteroid Ryugu.

Author

Matsumoto, Toru, primary, Noguchi, Takaaki, additional, Miyake, Akira, additional, Igami, Yohei, additional, Haruta, Mitsutaka, additional, Seto, Yusuke, additional, Miyahara, Masaaki, additional, Tomioka, Naotaka, additional, Saito, Hikaru, additional, Hata, Satoshi, additional, Harries, Dennis, additional, Takigawa, Aki, additional, Nakauchi, Yuusuke, additional, Tachibana, Shogo, additional, Nakamura, Tomoki, additional, Matsumoto, Megumi, additional, Ishii, Hope, additional, Bradley, John, additional, Ohtaki, Kenta, additional, Dobrică, Elena, additional, Leroux, Hugues, additional, Guillou, Corentin Le, additional, Jacob, Damien, additional, Peña, Francisco de la, additional, Laforet, Sylvain, additional, Marinova, Maya, additional, Langenhorst, Falko, additional, Beck, Pierre, additional, Phan, Thi, additional, Rebois, Rolando, additional, Abreu, Neyda, additional, Gray, Jennifer, additional, Zega, Thomas, additional, Zanetta, Pierre-Marie, additional, Thompson, Michelle, additional, Stroud, Rhonda, additional, Burgess, Katherine, additional, Cymes, Brittany, additional, Bridges, John, additional, Hicks, Leon, additional, Lee, Martin, additional, Daly, Luke, additional, Bland, Phil, additional, Zolensky, Michael, additional, Frank, David, additional, Martinez, James, additional, Tsuchiyama, Akira, additional, Yasutake, Masahiro, additional, Matsuno, Junya, additional, Okumura, Shota, additional, Mitsukawa, Itaru, additional, Uesugi, Kentaro, additional, Uesugi, Masayuki, additional, Takeuchi, Akihisa, additional, Sun, Mingqi, additional, Enju, Satomi, additional, Michikami, Tatsuhiro, additional, Yurimoto, Hisayoshi, additional, Okazaki, Ryuji, additional, Yabuta, Hikaru, additional, Naraoka, Hiroshi, additional, Sakamoto, Kanako, additional, Yada, Toru, additional, Nishimura, Masahiro, additional, Nakato, Aiko, additional, Miyazaki, Akiko, additional, Yogata, Kasumi, additional, Abe, Masanao, additional, Okada, Tatsuaki, additional, Usui, Tomohiro, additional, Yoshikawa, Makoto, additional, Saiki, Takanao, additional, Tanaka, Satoshi, additional, Terui, Fuyuto, additional, Nakazawa, Satoru, additional, Watanabe, Sei-ichiro, additional, and Tsuda, Yuichi, additional

Published
2023
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24. A dehydrated space-weathered skin cloaking the hydrated interior of Ryugu

Author

Noguchi, Takaaki, primary, Matsumoto, Toru, additional, Miyake, Akira, additional, Igami, Yohei, additional, Haruta, Mitsutaka, additional, Saito, Hikaru, additional, Hata, Satoshi, additional, Seto, Yusuke, additional, Miyahara, Masaaki, additional, Tomioka, Naotaka, additional, Ishii, Hope A., additional, Bradley, John P., additional, Ohtaki, Kenta K., additional, Dobrică, Elena, additional, Leroux, Hugues, additional, Le Guillou, Corentin, additional, Jacob, Damien, additional, de la Peña, Francisco, additional, Laforet, Sylvain, additional, Marinova, Maya, additional, Langenhorst, Falko, additional, Harries, Dennis, additional, Beck, Pierre, additional, Phan, Thi H. V., additional, Rebois, Rolando, additional, Abreu, Neyda M., additional, Gray, Jennifer, additional, Zega, Thomas, additional, Zanetta, Pierre-M., additional, Thompson, Michelle S., additional, Stroud, Rhonda, additional, Burgess, Kate, additional, Cymes, Brittany A., additional, Bridges, John C., additional, Hicks, Leon, additional, Lee, Martin R., additional, Daly, Luke, additional, Bland, Phil A., additional, Zolensky, Michael E., additional, Frank, David R., additional, Martinez, James, additional, Tsuchiyama, Akira, additional, Yasutake, Masahiro, additional, Matsuno, Junya, additional, Okumura, Shota, additional, Mitsukawa, Itaru, additional, Uesugi, Kentaro, additional, Uesugi, Masayuki, additional, Takeuchi, Akihisa, additional, Sun, Mingqi, additional, Enju, Satomi, additional, Takigawa, Aki, additional, Michikami, Tatsuhiro, additional, Nakamura, Tomoki, additional, Matsumoto, Megumi, additional, Nakauchi, Yusuke, additional, Abe, Masanao, additional, Arakawa, Masahiko, additional, Fujii, Atsushi, additional, Hayakawa, Masahiko, additional, Hirata, Naru, additional, Hirata, Naoyuki, additional, Honda, Rie, additional, Honda, Chikatoshi, additional, Hosoda, Satoshi, additional, Iijima, Yu-ichi, additional, Ikeda, Hitoshi, additional, Ishiguro, Masateru, additional, Ishihara, Yoshiaki, additional, Iwata, Takahiro, additional, Kawahara, Kousuke, additional, Kikuchi, Shota, additional, Kitazato, Kohei, additional, Matsumoto, Koji, additional, Matsuoka, Moe, additional, Mimasu, Yuya, additional, Miura, Akira, additional, Morota, Tomokatsu, additional, Nakazawa, Satoru, additional, Namiki, Noriyuki, additional, Noda, Hirotomo, additional, Noguchi, Rina, additional, Ogawa, Naoko, additional, Ogawa, Kazunori, additional, Okada, Tatsuaki, additional, Okamoto, Chisato, additional, Ono, Go, additional, Ozaki, Masanobu, additional, Saiki, Takanao, additional, Sakatani, Naoya, additional, Sawada, Hirotaka, additional, Senshu, Hiroki, additional, Shimaki, Yuri, additional, Shirai, Kei, additional, Sugita, Seiji, additional, Takei, Yuto, additional, Takeuchi, Hiroshi, additional, Tanaka, Satoshi, additional, Tatsumi, Eri, additional, Terui, Fuyuto, additional, Tsukizaki, Ryudo, additional, Wada, Koji, additional, Yamada, Manabu, additional, Yamada, Tetsuya, additional, Yamamoto, Yukio, additional, Yano, Hajime, additional, Yokota, Yasuhiro, additional, Yoshihara, Keisuke, additional, Yoshikawa, Makoto, additional, Yoshikawa, Kent, additional, Fukai, Ryohta, additional, Furuya, Shizuho, additional, Hatakeda, Kentaro, additional, Hayashi, Tasuku, additional, Hitomi, Yuya, additional, Kumagai, Kazuya, additional, Miyazaki, Akiko, additional, Nakato, Aiko, additional, Nishimura, Masahiro, additional, Soejima, Hiromichi, additional, Suzuki, Ayako I., additional, Usui, Tomohiro, additional, Yada, Toru, additional, Yamamoto, Daiki, additional, Yogata, Kasumi, additional, Yoshitake, Miwa, additional, Connolly, Harold C., additional, Lauretta, Dante S., additional, Yurimoto, Hisayoshi, additional, Nagashima, Kazuhide, additional, Kawasaki, Noriyuki, additional, Sakamoto, Naoya, additional, Okazaki, Ryuji, additional, Yabuta, Hikaru, additional, Naraoka, Hiroshi, additional, Sakamoto, Kanako, additional, Tachibana, Shogo, additional, Watanabe, Sei-ichiro, additional, and Tsuda, Yuichi, additional

Published
2022
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25. Oxygen isotopes of anhydrous primary minerals show kinship between asteroid Ryugu and comet 81P/Wild2

Author

1000050770278, Kawasaki, Noriyuki, Nagashima, Kazuhide, Sakamoto, Naoya, Matsumoto, Toru, Bajo, Ken-Ichi, Wada, Sohei, Igami, Yohei, Miyake, Akira, Noguchi, Takaaki, Yamamoto, Daiki, Russell, Sara S., Abe, Yoshinari, Aleon, Jerome, Alexander, Conel M. O'd, Amari, Sachiko, Amelin, Yuri, Bizzarro, Martin, Bouvier, Audrey, Carlson, Richard W., Chaussidon, Marc, Choi, Byeon-Gak, Dauphas, Nicolas, Davis, Andrew M., Di Rocco, Tommaso, Fujiya, Wataru, Fukai, Ryota, Gautam, Ikshu, Haba, Makiko K., Hibiya, Yuki, Hidaka, Hiroshi, Homma, Hisashi, Hoppe, Peter, Huss, Gary R., Ichida, Kiyohiro, Iizuka, Tsuyoshi, Ireland, Trevor R., Ishikawa, Akira, Ito, Motoo, Itoh, Shoichi, Kita, Noriko T., Kitajima, Kouki, Kleine, Thorsten, Komatani, Shintaro, Krot, Alexander N., Liu, Ming-Chang, Masuda, Yuki, McKeegan, Kevin D., Morita, Mayu, Motomura, Kazuko, Moynier, Frederic, Nakai, Izumi, Nguyen, Ann, Nittler, Larry, Onose, Morihiko, Pack, Andreas, Park, Changkun, Piani, Laurette, Qin, Liping, Schonbachler, Maria, Tafla, Lauren, Tang, Haolan, Terada, Kentaro, Terada, Yasuko, Usui, Tomohiro, Wadhwa, Meenakshi, Walker, Richard J., Yamashita, Katsuyuki, Yin, Qing-Zhu, Yokoyama, Tetsuya, Yoneda, Shigekazu, Young, Edward D., Yui, Hiroharu, Zhang, Ai-Cheng, Nakamura, Tomoki, Naraoka, Hiroshi, Okazaki, Ryuji, Sakamoto, Kanako, Yabuta, Hikaru, Abe, Masanao, Miyazaki, Akiko, Nakato, Aiko, Nishimura, Masahiro, Okada, Tatsuaki, Yada, Toru, Yogata, Kasumi, Nakazawa, Satoru, Saiki, Takanao, Tanaka, Satoshi, Terui, Fuyuto, Tsuda, Yuichi, Watanabe, Sei-Ichiro, Yoshikawa, Makoto, Tachibana, Shogo, Yurimoto, Hisayoshi, 1000050770278, Kawasaki, Noriyuki, Nagashima, Kazuhide, Sakamoto, Naoya, Matsumoto, Toru, Bajo, Ken-Ichi, Wada, Sohei, Igami, Yohei, Miyake, Akira, Noguchi, Takaaki, Yamamoto, Daiki, Russell, Sara S., Abe, Yoshinari, Aleon, Jerome, Alexander, Conel M. O'd, Amari, Sachiko, Amelin, Yuri, Bizzarro, Martin, Bouvier, Audrey, Carlson, Richard W., Chaussidon, Marc, Choi, Byeon-Gak, Dauphas, Nicolas, Davis, Andrew M., Di Rocco, Tommaso, Fujiya, Wataru, Fukai, Ryota, Gautam, Ikshu, Haba, Makiko K., Hibiya, Yuki, Hidaka, Hiroshi, Homma, Hisashi, Hoppe, Peter, Huss, Gary R., Ichida, Kiyohiro, Iizuka, Tsuyoshi, Ireland, Trevor R., Ishikawa, Akira, Ito, Motoo, Itoh, Shoichi, Kita, Noriko T., Kitajima, Kouki, Kleine, Thorsten, Komatani, Shintaro, Krot, Alexander N., Liu, Ming-Chang, Masuda, Yuki, McKeegan, Kevin D., Morita, Mayu, Motomura, Kazuko, Moynier, Frederic, Nakai, Izumi, Nguyen, Ann, Nittler, Larry, Onose, Morihiko, Pack, Andreas, Park, Changkun, Piani, Laurette, Qin, Liping, Schonbachler, Maria, Tafla, Lauren, Tang, Haolan, Terada, Kentaro, Terada, Yasuko, Usui, Tomohiro, Wadhwa, Meenakshi, Walker, Richard J., Yamashita, Katsuyuki, Yin, Qing-Zhu, Yokoyama, Tetsuya, Yoneda, Shigekazu, Young, Edward D., Yui, Hiroharu, Zhang, Ai-Cheng, Nakamura, Tomoki, Naraoka, Hiroshi, Okazaki, Ryuji, Sakamoto, Kanako, Yabuta, Hikaru, Abe, Masanao, Miyazaki, Akiko, Nakato, Aiko, Nishimura, Masahiro, Okada, Tatsuaki, Yada, Toru, Yogata, Kasumi, Nakazawa, Satoru, Saiki, Takanao, Tanaka, Satoshi, Terui, Fuyuto, Tsuda, Yuichi, Watanabe, Sei-Ichiro, Yoshikawa, Makoto, Tachibana, Shogo, and Yurimoto, Hisayoshi

Abstract

The extraterrestrial materials returned from asteroid (162173) Ryugu consist predominantly of low-temperature aqueously formed secondary minerals and are chemically and mineralogically similar to CI (Ivuna-type) carbonaceous chondrites. Here, we show that high-temperature anhydrous primary minerals in Ryugu and CI chondrites exhibit a bimodal distribution of oxygen isotopic compositions: 16O-rich (associated with refractory inclusions) and 16O-poor (associated with chondrules). Both the 16O-rich and 16O-poor minerals probably formed in the inner solar protoplanetary disk and were subsequently transported outward. The abundance ratios of the 16O-rich to 16O-poor minerals in Ryugu and CI chondrites are higher than in other carbonaceous chondrite groups but are similar to that of comet 81P/Wild2, suggesting that Ryugu and CI chondrites accreted in the outer Solar System closer to the accretion region of comets.

Published
2022

26. Behavior of chemically zoned acicular mullite fibers annealed at high temperature

Author

Igami, Yohei, Birkenstock, Johannes, Fischer, Reinhard X., and Schneider, Hartmut

Abstract

The synthetic analogue of the rare mineral mullite (solid solution VIAl2IV[Al2+2xSi2-2x]O10-x) is widely used in ceramics as “3/2-mullite” (x~0.25), whereas single crystals grown from melt are “2/1-mullites” (x~0.4) [1]. The investigated acicular mullite ceramic consists of single-crystalline fibers with high-Al mullite (M1) in the core and low-Al mullite (M2) in the rim [2,3], appearing as two distinct mullite phases in powder XRD patterns [2]. On annealing the as-prepared sample at 1550°C (24, 96, 192 and 384 h) the two zones gradually merge into one homogeneous phase [2]. Here, we present the details of this merging, investigating cross sections of fibers via TEM. Observed changes in a) width of the transition zone, b) relative lattice orientations of the two zones and c) lattice parameter a document progressive homogenization of the mullite, which is complete after 384h. Concurrently, we observed Si-rich, round to rectangular amorphous regions, probably from partial melting, most strikingly after 384 h. An increasing amount of Si-rich glass phase with annealing time would explain the overall increase of average Al-content in mullite which we observed in our XRD data [2]. We thank Prof. K.T. Faber (NW University, Evanston, IL/USA) for the samples, and the DFG for funding (Grant FI442/24-1). [1] R.X. Fischer & H. Schneider (2005), in Mullite (eds. H. Schneider, S. Komarneni), Weinheim: Wiley-VCH 1-46 [2] J. Birkenstock, Y. Igami, R.X. Fischer & H. Schneider (2019), Abstract GeoMünster 2019 [3] A.J. Pyzik, C.S. Todd & C. Han (2008), J. Eur. Cer. Soc. 28, 383-391

Published
2022
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27. High-temperature structural change and microtexture formation of sillimanite and its phase relation with mullite

Author

Igami, Yohei, Ohi, Shugo, Kogiso, Tetsu, Furukawa, Noboru, and Miyake, Akira

Subjects
TEM observation, sillimanite, synchrotron X-ray experiment, high-temperature phase relation, mullite
Abstract

Synchrotron powder X-ray diffraction (XRD) experiments and transmission electron microscopy (TEM) observations of heat-treated sillimanite at various pressures were conducted to clarify the detailed phase relation between sillimanite and mullite. Under TEM, heat-treated sillimanite frequently showed anti-phase boundary (APB)-like textures with a displacement vector of 1/2[001]sil. Additional scanning TEM energy-dispersive X-ray spectroscopy analysis of regions with APB-like texture showed that they were clearly enriched in Al and accompanied by very fine, Si-rich glass inclusions, which indicates that the APB-like textures are composed of fine mullite. Moreover, synchrotron XRD patterns of these samples clearly showed double peaks of newly formed mullite and remnant sillimanite, indicating that the compositional transformation from sillimanite to mullite and glass is discontinuous. We separately determined the cell parameters of the sillimanite and mullite from the XRD pattern and found that the b axial length of the sillimanite increased with the treatment temperature, reflecting disordering of tetrahedral Al and Si in the sillimanite. In contrast, the positions of the deconvoluted mullite peaks indicated that the a axial length of mullite decreased as experimental pressure increased, owing to enrichment of the Si component. By projecting the cell parameters onto the a–b axial plane, the detailed changes in the crystallographic state of the sillimanite and mullite could be easily and comprehensively identified. On the basis of our results, we propose a new P-T diagram for the Al2SiO5 system that shows the transformation boundary between sillimanite and mullite +SiO2-rich melt and the contour of the Al/Si order parameter of sillimanite., ファイル公開：2020-07-01

Published
2019

29. Crustal anorthosite formation by deep‐seated hydrothermal circulation beneath fast‐spreading axis: Constraints from chronological approach, Sr isotope, and fluid–chromite inclusion investigation

Author

Akizawa, Norikatsu, primary, Miyake, Akira, additional, Igami, Yohei, additional, Tsuchiyama, Akira, additional, Asanuma, Hisashi, additional, Kogiso, Tetsu, additional, Wakaki, Shigeyuki, additional, Ishikawa, Tsuyoshi, additional, Arai, Shoji, additional, Eom, Jiwon, additional, Kawahata, Hodaka, additional, Aze, Takahiro, additional, and Yokoyama, Yusuke, additional

Published
2021
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31. Additional file 1: of Drastic effect of shearing on graphite microtexture: attention and application to Earth science

Author

Kouketsu, Yui, Miyake, Akira, Igami, Yohei, Taguchi, Tomoki, Kagi, Hiroyuki, and Enami, Masaki

Abstract

Figure S1. STEMâ EDS mapping data. (a) STEM image of mapped area, (b) EDS spectrum of the entire mapped area. (c) to (f) shows element maps of carbon (C), silicon (Si), aluminum (Al), and oxygen (O), respectively. Only C was detected in the map area, and impurities such as Si, Al, and O were not detected. In the EDS spectrum, small peaks of Si, Fe, and Co peaks are derived from pole piece and/or TEM sample holder, Ga and Pt peaks were derived at the FIB process, and Cu peaks were derived from the sample holder. (PDF 133 kb)

Published
2019
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42. Significance of an amorphous SiO2 phase in a pseudomorph after coesite enclosed in garnet from ultrahigh‐pressure eclogite, Su–Lu Belt, eastern China.

Author

Taguchi, Tomoki, Miyake, Akira, Enami, Masaki, and Igami, Yohei

Subjects
AMORPHOUS substances, TRANSMISSION electron microscopes, RAMAN spectroscopy, SUPERCRITICAL fluids, PHASE transitions
Abstract

Abstract: Here, we report the first discovery of an amorphous SiO2 phase (APSI phase) in a pseudomorph after coesite included in garnet from an ultrahigh‐pressure (UHP) eclogite from the Su–Lu metamorphic belt, eastern China. Using transmission electron microscopy, Raman spectroscopy and selected area electron diffraction, we show that the internal structure of the pseudomorph consists of an APSI phase with nano/submicrocrystalline particles of quartz and a polycrystalline K‐bearing fibrous sheet‐silicate phase (KFSS phase). The APSI phase‐bearing aggregates included in the garnet might have formed by reactions involving a supercritical fluid during exhumation by the following processes: (1) the development of radial cracks within the host garnet by the phase transition of coesite to quartz; (2) the decomposition of a part of the pseudomorph following infiltration of supercritical fluid; (3) the precipitation of the KFSS phase from the fluid phase during subsequent exhumation and cooling, which was likely promoted by a change in the metamorphic fluid from supercritical and/or subcritical to aqueous fluid; and (4) the rapid precipitation of the APSI phase under a metastable (non‐equilibrium) state, such as quenching, during a later stage of the exhumation. Whether the APSI phase generally formed during exhumation and survived widely throughout the Su‐Lu terrane is unknown. However, the presence of the APSI phase in a UHP eclogite provides new insight into the geodynamic phenomena occurring at continental collision zones. [ABSTRACT FROM AUTHOR]

Published
2018
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43. Microscopic slickenside as a record of weak shock metamorphism in the surface layer of asteroid Ryugu.

Author

Miyahara, Masaaki, Noguchi, Takaaki, Matsumoto, Toru, Tomioka, Naotaka, Miyake, Akira, Igami, Yohei, Seto, Yusuke, Haruta, Mitsutaka, Saito, Hikaru, Hata, Satoshi, Ishii, Hope A., Bradley, John P., Ohtaki, Kenta K., Dobrică, Elena, Leroux, Hugues, Le Guillou, Corentin, Jacob, Damien, Peña, Francisco, Laforet, Sylvain, and Mouloud, Bahae‐Eddine

Subjects
*SHEAR (Mechanics), *TRANSMISSION electron microscopy, *SCANNING electron microscopy, *SURFACE morphology, *PHYLLOSILICATES, *ASTEROIDS
Abstract

The surface morphology of regolith grains from the C‐type asteroid Ryugu was studied in search of evidence of impact events on the asteroid. Scanning electron microscopy revealed that ~8% of C0105‐042 Ryugu grains have a smooth surface on one side of the grains. One of these grains has striated linear grooves (striations) on its smooth surface. Transmission electron microscopy of the grain showed that a porous fine‐grained Mg‐Fe phyllosilicate assemblage, which is the main component of Ryugu grains, is compacted near the smooth surface. The smooth surface with striations closely resembles a slickenside, a characteristic texture found in terrestrial fault rocks formed by shear deformation. There is no evidence of melting/decomposition in the Mg‐Fe phyllosilicates near the smooth surface, indicating that the shear heating temperature is less than ~1100 K. Assuming that the average length of the striations corresponds to the minimum displacement of the micro‐fault, the shock pressure recorded in the C0105‐042 Ryugu grain is estimated to be <~4.5 GPa by a fault mechanics calculation. The shock pressures of C0105‐042, together with those of C0014 (~2 GPa) and C0055 (>~3.9 GPa) in previous studies suggest that the impact velocities recorded in these grains are < ~0.89–1.63 km s−1. Based on the impact velocities, these grains may record an impact event that occurred when asteroid Ryugu was in the orbit in Main Belt. [ABSTRACT FROM AUTHOR]

Published
2024
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44. A history of mild shocks experienced by the regolith particles on hydrated asteroid Ryugu

Author

Tomioka, Naotaka, Yamaguchi, Akira, Ito, Motoo, Uesugi, Masayuki, Imae, Naoya, Shirai, Naoki, Ohigashi, Takuji, Kimura, Makoto, Liu, Ming-Chang, Greenwood, Richard C., Uesugi, Kentaro, Nakato, Aiko, Yogata, Kasumi, Yuzawa, Hayato, Kodama, Yu, Hirahara, Kaori, Sakurai, Ikuya, Okada, Ikuo, Karouji, Yuzuru, Okazaki, Keishi, Kurosawa, Kosuke, Noguchi, Takaaki, Miyake, Akira, Miyahara, Masaaki, Seto, Yusuke, Matsumoto, Toru, Igami, Yohei, Nakazawa, Satoru, Okada, Tatsuaki, Saiki, Takanao, Tanaka, Satoshi, Terui, Fuyuto, Yoshikawa, Makoto, Miyazaki, Akiko, Nishimura, Masahiro, Yada, Toru, Abe, Masanao, Usui, Tomohiro, Watanabe, Sei-ichiro, Tsuda, Yuichi, Tomioka, Naotaka, Yamaguchi, Akira, Ito, Motoo, Uesugi, Masayuki, Imae, Naoya, Shirai, Naoki, Ohigashi, Takuji, Kimura, Makoto, Liu, Ming-Chang, Greenwood, Richard C., Uesugi, Kentaro, Nakato, Aiko, Yogata, Kasumi, Yuzawa, Hayato, Kodama, Yu, Hirahara, Kaori, Sakurai, Ikuya, Okada, Ikuo, Karouji, Yuzuru, Okazaki, Keishi, Kurosawa, Kosuke, Noguchi, Takaaki, Miyake, Akira, Miyahara, Masaaki, Seto, Yusuke, Matsumoto, Toru, Igami, Yohei, Nakazawa, Satoru, Okada, Tatsuaki, Saiki, Takanao, Tanaka, Satoshi, Terui, Fuyuto, Yoshikawa, Makoto, Miyazaki, Akiko, Nishimura, Masahiro, Yada, Toru, Abe, Masanao, Usui, Tomohiro, Watanabe, Sei-ichiro, and Tsuda, Yuichi

Abstract

Micrometeorites, a possible major source of Earth’s water, are thought to form from explosive dispersal of hydrated chondritic materials during impact events on their parental asteroids. However, this provenance and formation mechanism have yet to be directly confirmed using asteroid returned samples. Here, we report evidence of mild shock metamorphism in the surface particles of asteroid Ryugu based on electron microscopy. All particles are dominated by phyllosilicates but lack dehydration textures, which are indicative of shock-heating temperatures below ~500 °C. Microfault-like textures associated with extensively shock-deformed framboidal magnetites and a high-pressure polymorph of Fe–Cr–sulfide have been identified. These findings indicate that the average peak pressure was -2 GPa. The vast majority of ejecta formed during impact on Ryugu-like asteroids would be hydrated materials, larger than a millimetre, originating far from the impact point. These characteristics are inconsistent with current micrometeorite production models, and consequently, a new formation mechanism is required.

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