火星の季節的な南極の氷冠の半透明なスラブ氷の下の亜化によって形成されたCO2ジェット
Hugh H Kieffer1, Philip R Christensen, Timothy N Titus
1Celestial Reasonings, Carson City, Nevada 89703, USA.
Nature
|August 18, 2006
まとめ
火星の極地上の暗い斑点とチャネルは,季節的な二酸化炭素の氷帽を通って噴出したCO2ガスが形成され,暗い粒状の物質を表面に持ち上げます. これらのユニークな火星の地質学的過程は,地球上で観察されたものとは異なります.
科学分野:
- 惑星科学は惑星科学である.
- 地質学 地質学 地質学
- リモートセンシング (リモートセンサー)
背景:
- 火星の極地層は,二酸化炭素 (CO2) の氷の形成と亜高化とともに,動的な季節的変化を示しています.
- 異常な暗い斑点,扇風機,チャネルは,南極のCO2氷帽が後退する際に現れます.
- これらの表面の特徴と関連するチャネルの起源は不確かである.
研究 の 目的:
- CO2の氷冠の撤退中に観測された暗い斑点と扇風機の性質を調査する.
- ラディアルチャネルネットワークの形成に起因するプロセスを決定する.
主な方法:
- 火星の南極地域の赤外線と可視光観測.
- 表面温度と材料の性質を分析する.
主要な成果:
- ダークスポットとファンは二酸化炭素の氷の温度を維持し,氷の表面上の粒状物質であることを示しています.
- 二酸化炭素の氷冠の底部からの亜熱化により,高圧ガスが生成されます.
- ガス圧により氷が破裂し,CO2の噴出口が形成され,粒状物質が放出され,運河が侵食される.
結論:
- 観測された火星の表面の特徴は,季節的なCO2氷帽内の地下ガス圧によって形成されています.
- これらの特徴は,粒状物質を輸送し,チャネルを作り出すCO2ガスの排気によるものです.
- スポットとチャネルの形成のための提案されたメカニズムは,火星に特有のものです.
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