火星の南極付近で発見された露水氷
Timothy N Titus1, Hugh H Kieffer, Phillip R Christensen
1Branch of Astrogeology, U.S. Geological Survey, 2255 North Gemini Drive, Flagstaff, AZ 86001, USA. ttitus@usgs.gov
まとめ
マース・オデッセイ マース・オデッセイ
科学分野:
- 惑星科学は惑星科学である.
- 火星科学 火星科学
- 天体生物学 アストロバイオロジー
背景:
- 火星の南極はダイナミックな地域です.
- その構成を理解することは,火星の気候の歴史を理解するための鍵です.
- 以前のミッションでは,地表の下の氷の存在が示唆されていた.
研究 の 目的:
- 表面水の氷の存在と範囲を調査するために.
- 露出したH2O氷の兆候について熱データを分析する.
- 表面の氷が広範囲に広がっているかどうかを判断するために.
主な方法:
- 火星オデッセイ熱放出イメージングシステム (THEMIS) のデータを活用しています.
- 熱シグネチャーと温度トレンドを分析する.
- THEMISのデータと,Mars Global Surveyor Thermal Emission Spectrometer (TES) の観測を相関させる. 火星地球測量機の熱放出スペクトロメーター (TES) の観測と相関する. 火星地球測量機の熱放出スペクトロメーター (TES) の観測と相関する. 火星地球測量機の熱放出スペクトロメーター (TES) の観測と相関する.
主要な成果:
- 南極帽の縁付近で露出した水氷 (H2O) が発見された.
- 火星の夏の間,乾燥土壌が予想よりも涼しい地域が特定されました.
- 熱データによると,表面上のH2O氷が広範囲に広がっていることが示されています.
結論:
- 表面の水氷は,火星の南極点に存在し,露出しています.
- THEMISのデータは,氷に一致する季節的および昼間の気温異常を確認しています.
- 証拠によると,H2Oの氷は,CO2上限の周りに,そしてその下にも広く広がっている.
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