Incipient space weathering observed on the surface of itokawa dust particles

T. Noguchi, T. Nakamura, M. Kimura, M. E. Zolensky, M. Tanaka, T. Hashimoto, M. Konno, A. Nakato, T. Ogami, A. Fujimura, M. Abe, T. Yada, T. Mukai, M. Ueno, T. Okada, K. Shirai, Y. Ishibashi, R. Okazaki

研究成果: Contribution to journalArticle査読

188 被引用数 (Scopus)


The reflectance spectra of the most abundant meteorites, ordinary chondrites, are different from those of the abundant S-type (mnemonic for siliceous) asteroids. This discrepancy has been thought to be due to space weathering, which is an alteration of the surfaces of airless bodies exposed to the space environment. Here we report evidence of space weathering on particles returned from the S-type asteroid 25143 Itokawa by the Hayabusa spacecraft. Surface modification was found in 5 out of 10 particles, which varies depending on mineral species. Sulfur-bearing Fe-rich nanoparticles exist in a thin (5 to 15 nanometers) surface layer on olivine, low-Ca pyroxene, and plagioclase, which is suggestive of vapor deposition. Sulfur-free Fe-rich nanoparticles exist deeper inside (<60 nanometers) ferromagnesian silicates. Their texture suggests formation by metamictization and in situ reduction of Fe 2+.

出版ステータス出版済み - 8 26 2011

All Science Journal Classification (ASJC) codes

  • 一般


「Incipient space weathering observed on the surface of itokawa dust particles」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。