火星の南極の氷の特性を示すサブリメーションモデル
Shane Byrne1, Andrew P Ingersoll
1Division of Geological and Planetary Sciences, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA.
Science (New York, N.Y.)
|February 15, 2003
まとめ
火星の大気は火星の大気です.
科学分野:
- 惑星科学は惑星科学である.
- 大気科学 大気科学
- 地質学 地質学 地質学
背景:
- 火星の大気は主に二酸化炭素で構成されています.
- 以前の研究では,大きな二酸化炭素貯蔵庫が大気組成をコントロールしていると示唆されていた.
- 火星の大気調節における極地貯水池の役割は議論されている.
研究 の 目的:
- 火星に巨大な二酸化炭素の貯蔵庫があるという説に異議を唱えるためだ.
- 火星の大気中の二酸化炭素循環の代替モデルを提案する.
- 火星の南極点の組成と動態を調査するために.
主な方法:
- 火星の南極点の円形低谷の計算モデルを活用して.
- 火星オデッセイミッションからの熱赤外線データを分析しています.
- 二酸化炭素の氷と水の氷層の相互作用を調査する.
主要な成果:
- 北極の二酸化炭素貯蔵庫は,以前に推定されたよりもはるかに小さい可能性が高い.
- 約8メートルの厚さの二酸化炭素の氷層が侵食されています.
- 地下水の氷は,二酸化炭素の氷の亜化によって露出しています.
- このプロセスは,観測された熱赤外線シグネチャーと一致しています.
結論:
- 極の小さな貯水池は,火星の大気の長期的バッファとして機能することはできません.
- 観測された特徴は,二酸化炭素の氷のエッチングのダイナミックなプロセスを示唆しています.
- 火星の大気中の二酸化炭素は,これまで考えられていたこととは異なるメカニズムによって調節されている可能性があります.
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