@article{58401bfa86774f32943a4db9bb06db0f,
title = "Sample collection from asteroid (162173) Ryugu by Hayabusa2: Implications for surface evolution",
abstract = "The near-Earth asteroid (162173) Ryugu is thought to be a primitive carbonaceous object that contains hydrated minerals and organic molecules. We report sample collection from Ryugu{\textquoteright}s surface by the Hayabusa2 spacecraft on 21 February 2019. Touchdown images and global observations of surface colors are used to investigate the stratigraphy of the surface around the sample location and across Ryugu. Latitudinal color variations suggest the reddening of exposed surface material by solar heating and/or space weathering. Immediately after touchdown, Hayabusa2{\textquoteright}s thrusters disturbed dark, fine grains that originate from the redder materials. The stratigraphic relationship between identified craters and the redder material indicates that surface reddening occurred over a short period of time. We suggest that Ryugu previously experienced an orbital excursion near the Sun.",
author = "T. Morota and S. Sugita and Y. Cho and M. Kanamaru and E. Tatsumi and N. Sakatani and R. Honda and N. Hirata and H. Kikuchi and M. Yamada and Y. Yokota and S. Kameda and M. Matsuoka and H. Sawada and C. Honda and T. Kouyama and K. Ogawa and H. Suzuki and K. Yoshioka and M. Hayakawa and N. Hirata and M. Hirabayashi and H. Miyamoto and T. Michikami and T. Hiroi and R. Hemmi and Barnouin, {O. S.} and Ernst, {C. M.} and K. Kitazato and T. Nakamura and L. Riu and H. Senshu and H. Kobayashi and S. Sasaki and G. Komatsu and N. Tanabe and Y. Fujii and T. Irie and M. Suemitsu and N. Takaki and C. Sugimoto and K. Yumoto and M. Ishida and H. Kato and K. Moroi and D. Domingue and P. Michel and C. Pilorget and T. Iwata and M. Abe and M. Ohtake and Y. Nakauchi and K. Tsumura and H. Yabuta and Y. Ishihara and R. Noguchi and K. Matsumoto and A. Miura and N. Namiki and S. Tachibana and M. Arakawa and H. Ikeda and K. Wada and T. Mizuno and C. Hirose and S. Hosoda and O. Mori and T. Shimada and S. Soldini and R. Tsukizaki and H. Yano and M. Ozaki and H. Takeuchi and Y. Yamamoto and T. Okada and Y. Shimaki and K. Shirai and Y. Iijima and H. Noda and S. Kikuchi and T. Yamaguchi and N. Ogawa and G. Ono and Y. Mimasu and K. Yoshikawa and T. Takahashi and Y. Takei and A. Fujii and S. Nakazawa and F. Terui and S. Tanaka and M. Yoshikawa and T. Saiki and S. Watanabe and Y. Tsuda",
note = "Funding Information: T.Mo., S.Su., N.S., S.Ka., M.M., S.Sa., M.Ab., R.N., A.M., K.W., and S.W. were supported by KAKENHI from the Japan Society for the Promotion of Science (JSPS) (grant nos. 17H06459, 19H01951, 17H01175, 17KK0097, 19H00727, 18H01267, 18K11610, 19K03955, 16H04044, and 19K03958). This study was supported by the JSPS Core-to-Core program “International Network of Planetary Sciences.” T.H. acknowledges funding support from NASA{\textquoteright}s EW and PDART programs. M.Hi. acknowledges support from NASA/Solar System Workings (NNH17ZDA001N/80NSSC19K0548) and Auburn Univ.'s intramural research grant. O.S.B. acknowledges support from OSIRIS-REx under contract NNM10AA11C, issued through the NASA New Frontiers Program. D.D. and C.M.E. acknowledge funding through the NASA Hayabusa2 Participating Scientist Program. P.M. acknowledges funding from the French space agency CNES; from Academies of Excellence: Complex systems and Space, environment, risk, and resilience, part of the IDEX JEDI of the Universit{\'e} C{\^o}te d{\textquoteright}Azur; and from the European Union{\textquoteright}s Horizon 2020 research and innovation program under grant agreement no. 870377 (project NEO-MAPP). Author contributions: T.Mo. coordinated coauthor contributions, led the ONC data analyses and interpretations, and wrote the paper with contributions from S.Su., N.H. (Aizu), and S.Ka. ONC data acquisitions and reductions: R.Ho., N.S., Y.Yo., M.Ya., S.Su., T.Mo., S.Ka., H.Sa., M.M., T.K., E.T., C.Ho., K.O., H.Su., K.Yoshio., M.Ha., Y.C., Y.Ii., N.Tak., C.S., K.Yu., M.I., H.Ka., K.Mo., and D.D.; Spectral analysis: E.T., D.D., R.Ho., Y.Yo., S.Su., and T.Mo.; Crater statistics and geomorphology analyses: T.Mo., Y.C., M.K., N.H. (Kobe), O.S.B., C.M.E., E.T., and S.Su.; Shape modeling: N.H. (Kobe), N.H. (Aizu), O.S.B., C.M.E., R.N., Y.S., S.W.; NIRS3 data acquisitions and reductions: K.K., T.N., L.R., C.P., T.Iw., M.Ab., M.Oh., Y.N., and K.T.; Landing site characterization: Y.Ts., S.W., T.Sa., S.Ki., T.Y., N.O., Y.Ya., Y.S., K.S., N.H. (Kobe), K.O., K.K., N.H. (Aizu), K.W., H.Yab., Y.Is., R.N., T.Mo., N.S., K.Ma., H.Se., R.Ho., E.T., Y.Yo., C.Ho., T.Mic., M.M., A.M., N.Tan., Y.F., T.Ir., M.S.; Science operations of spacecraft: T.Miz., C.Hi., S.H., O.M., T.Sh., S.So., R.T., H.Yan., M.Ha., T.Iw., M.Ab., H.Sa., M.Oz., H.T., Y.Ya., T.O., Y.S., K.S., Y.Ii., H.N., S.Ki., T.Y., N.O., G.O., Y.M., K.Yoshik., T.T., Y.Ta., A.F., S.N., F.T., S.Tan., M.Yo., T.Sa., S.W., and Y.Ts.; Project administration: S.W., M.Yo., S.Tac., K.K., S.Su., T.O., N.N., M.Ar., M.Ab., H.I., S.Tan., S.N., F.T., T.Sa., and Y.Ts.; and Interpretation and writing contribution: T.Mo., S.Su., R.Ho., E.T., Y.C., Y.Yo., S.Ka., N.S., M.M., M.Ya., N.H. (Kobe), N.H. (Aizu), S.W., T.Mic., M.Hi., T.H., R.He., G.K., S.Sa., T.N., K.W., N.Tan., C.M.E., D.D., and P.M. All authors discussed the results and commented on the manuscript. Publisher Copyright: {\textcopyright} 2020 American Association for the Advancement of Science. All rights reserved.",
year = "2020",
month = may,
day = "8",
doi = "10.1126/science.aaz6306",
language = "English",
volume = "368",
pages = "654--659",
journal = "Science",
issn = "0036-8075",
publisher = "American Association for the Advancement of Science",
number = "6491",
}