月の南極にあるシャクルトンクレーター内の揮発性分布の制約
Maria T Zuber1, James W Head, David E Smith
1Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. zuber@mit.edu
Nature
|June 23, 2012
まとめ
月の南極の近くにあるシャクルトンクレーターには,揮発性物質がある可能性があります. 新しいデータによると,その壁は床よりも新鮮で,氷が存在する可能性を示唆していますが,下り坂のレゴリティの動きも可能です.
科学分野:
- 月面地質学 月面地質学
- 惑星科学は惑星科学である.
- リモートセンシングによる遠隔感知
背景:
- 月の南極の近くにあるシャクルトンクレーターは,揮発性物質のための潜在的な冷たい罠です.
- シャクルトンクレーターの揮発性物質の含有量に関する以前の研究では,矛盾する結果が得られた.
- シャクルトンクレーターの構成を理解することは,月探査の鍵です.
研究 の 目的:
- シャクルトンクレーターの地質学的特徴と揮発性可能性を調査するために.
- シャクルトンクレーターの揮発性物質の存在に関する矛盾した解釈を解決するために.
- 先進的なリモートセンシングデータを用いてシャクルトンクレーターの地表と地下の構成を分析する.
主な方法:
- 月面探査軌道 (LRO) に搭載された月面軌道レーザー高度計 (LOLA) による観測.
- 壁と床の保存を含むクレーター形態の分析.
- 表面の明るさを評価するために,1064ナノメートルの波長でのフォトメトリック分析.
主要な成果:
- シャクルトンクレーター (Shackleton crater) は,古くから保存されているシンプルなクレーターです.
- 内部壁は地質学的にクレーターの床と縁よりも新鮮です.
- クレーター床の堆積物は,円周と同じくらい古く,形成後の堆積が最小であることを示す.
- シェックルトンの床は周囲の地形よりも明るいが,内部壁よりも明るくはない. 1,064 nm.
結論:
- クレーター壁のレゴリスの下り坂の動きは,より新鮮な物質を露出させ,主に観測を説明します.
- シャドーイングによる宇宙気象の減少は,より明るいクレーター床の単純な説明を提供します.
- 表面の氷の薄い層 (約. 1マイクロメートルの厚さ,20%の濃度) は,床の明るさの合理的な代替説明である.
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