TY - JOUR
T1 - Formation and evolution of carbonaceous asteroid Ryugu
T2 - Direct evidence from returned samples
AU - Nakamura, T.
AU - Matsumoto, M.
AU - Amano, K.
AU - Enokido, Y.
AU - Zolensky, M. E.
AU - Mikouchi, T.
AU - Genda, H.
AU - Zolotov, M. Y.
AU - Potin, S. M.
AU - More Authors, null
PY - 2023
Y1 - 2023
N2 - Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.
AB - Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.
UR - http://www.scopus.com/inward/record.url?scp=85148772806&partnerID=8YFLogxK
U2 - 10.1126/science.abn8671
DO - 10.1126/science.abn8671
M3 - Article
C2 - 36137011
AN - SCOPUS:85148772806
SN - 0036-8075
VL - 379
JO - Science (New York, N.Y.)
JF - Science (New York, N.Y.)
IS - 6634
M1 - eabn8671
ER -