Hisayoshi Yurimoto, Ken-ichi Abe, Masanao Abe, Mitsuru Ebihara, Akio Fujimura, Minako Hashiguchi, Ko Hashizume, Trevor R Ireland, Shoichi Itoh, Juri Katayama, Chizu Kato, Junichiro Kawaguchi, Noriyuki Kawasaki, Fumio Kitajima, Sachio Kobayashi, Tatsuji Meike, Toshifumi Mukai, Keisuke Nagao, Tomoki Nakamura, Hiroshi Naraoka, Takaaki Noguchi, Ryuji Okazaki, Changkun Park, Naoya Sakamoto, Yusuke Seto, Masashi Takei, Akira Tsuchiyama, Masayuki Uesugi, Shigeyuki Wakaki, Toru Yada, Kosuke Yamamoto, Makoto Yoshikawa, Michael E Zolensky
Science (New York, N.Y.) 333(6046) 1116-9 2011年8月26日
Meteorite studies suggest that each solar system object has a unique oxygen isotopic composition. Chondrites, the most primitive of meteorites, have been believed to be derived from asteroids, but oxygen isotopic compositions of asteroids themselves have not been established. We measured, using secondary ion mass spectrometry, oxygen isotopic compositions of rock particles from asteroid 25143 Itokawa returned by the Hayabusa spacecraft. Compositions of the particles are depleted in (16)O relative to terrestrial materials and indicate that Itokawa, an S-type asteroid, is one of the sources of the LL or L group of equilibrated ordinary chondrites. This is a direct oxygen-isotope link between chondrites and their parent asteroid.