タイトル（掲載誌）宇宙航空研究開発機構特別資料 = JAXA Special Publication: The Second Open Competition for the Hayabusa Asteroidal Sample Preliminary Examination Team (HASPET)
一般注記We have studied the mineralogy and petrology of the Hayabusa test samples, 3A and 3B, using an optical microscope, a Scanning Electron Microscope (SEM) and an electron probe micro-analyzer. We also used an analytical field emission SEM and an analytical transmission electron microscope to obtain information especially at high magnification. The 3A sample is powder composed of particles (less than 150 micrometer in diameter) that consist mainly of fine grains of Fe-rich olivine, low-Ca pyroxene and lesser amounts of high-Ca pyroxene and plagioclase. The 3B sample is composed of rounded to subrounded particles (0.2-2.3 mm in diameter) that consist mainly of Fe-Ni metal and lesser amounts of Fe-rich olivine and low-Ca pyroxene. Both 3A and 3B particles contain materials that are analogous in texture to chondrules in chondrites. Fe-rich olivine and low-Ca pyroxene in both 3A and 3B are highly homogeneous in composition. Although the general appearance and the relative abundances of constituent minerals are different between 3A and 3B, most constituent minerals occur in common and have very similar compositions that closely resemble those of the counterparts in equilibrated H ordinary chondrites. The results suggest that 3A is made of a silicate-rich fraction of an equilibrated H chondrite and 3B is made of a metal-rich fraction of an equilibrated H chondrite. 3B particles may correspond to individual silicate-bearing metal grains in an H chondrite. Although precise determination of petrologic type is difficult because of very small particle size, we suggest that the petrologic type of both 3A and 3B is relatively low.
資料番号: AA0063920003
レポート番号: JAXA-SP-05-021E
連携機関・データベース国立情報学研究所 : 学術機関リポジトリデータベース（IRDB）（機関リポジトリ）
提供元機関・データベース宇宙航空研究開発機構 : 宇宙航空研究開発機構リポジトリ