エンケラドスの表面の構成と物理的性質
Robert H Brown1, Roger N Clark, Bonnie J Buratti
1Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA.
Science (New York, N.Y.)
|March 11, 2006
まとめ
カッシーニは,カッシーニから
科学分野:
- 惑星科学 惑星科学
- 天体生物学 アストロバイオロジー
- スペクトル顕微鏡検査です.
背景:
- 土星の衛星エンケラドスは,ユニークな表面組成と熱異常を示しています.
- "タイガーストライプ"として知られる南極地域は特に興味深い.
研究 の 目的:
- カッシーニの視覚・赤外線マッピングスペクトロメーター (VIMS) を使用してエンケラドスの表面構成と熱的性質を分析する.
- 重要な分子の存在を調査し,特定の地域における温度限界を決定する.
主な方法:
- カッシーニが2005年にエンケラドスの3回通過したデータを活用した.
- 視覚および赤外線マッピングスペクトロメーター (VIMS) を用いてスペクトル分析を行いました.
主要な成果:
- エンケラドスの表面は主に水氷で,南極の近くには軽い有機物とCO2がある.
- 大気中の一酸化炭素 (CO) の上限値は,降水可能なナノメートル5で,表面積分のアンモニア (NH3) は2%で設定されました.
- タイガーストライプ地域での気温は,上限140ケルヴィンに制限されました.
結論:
- エンケラドスの表面の組成,特にトラのストライプは,その地質学的活動についての洞察を提供します.
- 導出されたCOとNH3の限界値は,エンケラドスの大気と表面モデルに制約を与える.
- タイガーストライプからの熱データから,局所的なエネルギー源またはプロセスが示唆されています.
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