エウロパの表面下には海が存在していたという証拠があります.
M H Carr1, M J Belton, C R Chapman
1US Geological Survey, Menlo Park, California 94025, USA. carr@astmnl.wr.usgs.gov
Nature
|February 5, 1998
まとめ
木星の衛星欧州の高解像度ガリレオの画像は,移動氷山の証拠を明らかにし,浅い地下海の存在を裏付けている. この発見は,ヨーロッパの地質学的な活動と潜在的な居住可能性に関する新しい洞察を提供します.
科学分野:
- 惑星科学は惑星科学である.
- 天体生物学 アストロバイオロジー
- 地質学 地質学 地質学
背景:
- 顕微鏡と重力データによると,ヨーロッパには150キロメートルの氷の地殻と岩石の内部があることを示唆しています.
- ヴォイジャー号の画像は,線形 (lineae) と若い地形を示し,地下液体の水層を暗示しています.
- 以前の低解像度画像 (<2 km/pixel) は,地表下海の確認を妨げていた.
研究 の 目的:
- 高解像度のガリレオ宇宙船のエウロパの画像を提示する.
- 移動氷山と浅い地下水の証拠を調査する.
- これらの現象の広範な性質を評価する.
主な方法:
- 高解像度 (54 m/pixel) のガリレオ宇宙船によるヨーロッパの画像の分析.
- より大きな地域をカバーする低解像度の画像の調査.
主要な成果:
- 移動可能な"氷山"がエウロパの表面で発見された.
- 詳細な地形形態学は,過去または現在,浅い液体の水を強く支持しています.
- 観測により,これらの現象はヨーロッパ全土に広がっていることが示唆されています.
結論:
- 高解像度の画像は,エウロパの浅い地下水が存在するという説得力のある証拠を提供します.
- この発見は,潮による加熱と,地表の下の海によって引き起こされる地質学的活動を含むモデルを裏付けている.
- エウロパのダイナミックな氷の殻と液体の水の可能性は,その天体生物学的な重要性を高めています.
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