小惑星24Themisの表面に水氷と有機物質が発見されました
Humberto Campins1, Kelsey Hargrove, Noemi Pinilla-Alonso
1University of Central Florida, PO Box 162385, Orlando, Florida 32816-2385, USA. campins@physics.ucf.edu
Nature
|April 30, 2010
まとめ
小惑星24テミスは,表面の氷と有機化合物が多く存在することを示し,小惑星が地球に水を届けたという理論を支持しています. この発見は,惑星の水の起源に関する新しい洞察を提供します.
科学分野:
- 惑星科学は惑星科学である.
- 天文学 (astronomy) 天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは
- 天体生物学 アストロバイオロジー
背景:
- 地球の水は,月が形成された後の小惑星によってもたらされたのかもしれない.
- いくつかの小惑星の彗星のような活動は,水の氷の存在を示唆しています.
- 以前の研究では,小惑星の水氷を直接測定しなかったが,推論された.
研究 の 目的:
- 小惑星24テミスの組成を調べるために.
- 小惑星に水氷と有機化合物の存在を確認するために.
- 水の起源と地球への水の供給を理解する.
主な方法:
- 赤外線スペクトロスコピーは,小惑星24 Themis.の表面を分析するために使用されました.
- スペクトルデータは,様々な化合物の既知のスペクトルシグネチャーと比較した.
- 独立した結果は,スペクトルの特徴の識別を検証するために使用されました.
主要な成果:
- 赤外線スペクトルは,小惑星24Themis.の水氷と有機化合物の存在を明らかにしました.
- 小惑星24テミスは,他の小惑星と比較してユニークなスペクトル特性を表しています.
- 広範囲に広がった表面の氷は,3.2AUのサブリメーション率を考慮して予想外です.
結論:
- 小惑星24テミスは,表面の氷と有機物質が豊富です.
- この発見は,小惑星が地球に水を運んだという仮説を裏付けている.
- 地下貯水池とインパクトガーデニングは,観測された地表氷の合理的な説明である.
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