カリストの内部液体の水の海の凍結に対する安定性

J Ruiz¹

¹Departamento de Geodinámica, Facultad de Ciencias Geológicas, and Seminar on Planetary Sciences, Universidad Complutense de Madrid, Spain. jaruiz@eucmax.sim.ucm.es

Nature

|July 27, 2001

まとめ

カリスト・カリスト

科学分野:

惑星科学は惑星科学である.
地質物理学地質物理学とは地質物理学です.
天体生物学アストロバイオロジー

背景:

木星の衛星カリストの誘導磁場は,地表下海の存在を示唆している.
現存するモデルでは,潮による加熱が不十分であるため,海洋の生存を説明するのに苦労しています.
以前の研究では,氷殻の不安定性が示され,海が凍結することにつながった.

研究の目的:

カリストの氷殻の安定性を再評価する.
潜在的地下海洋の長期的な生存を調査する.
現実的な氷の粘度モデルを組み込む.

主な方法:

ストレス依存の非ニュートンの氷の粘度モデルを適用した.
固体コンベクションに対する外側の氷殻の安定性を分析した.
ニュートンの粘度を用いた以前のモデルと結果を比較した.

主要な成果:

外側の氷殻は,現実的な粘度で,コンベクションに対して安定しています.
この安定性は,地表の下の海洋の長期的な生存を可能にします.
海洋を説明するために,防凍剤や異常な条件の必要性を排除します.

結論:

カリストの地下海洋は,安定した氷殻のダイナミクスを考えると,妥当である.
現実的な氷の物理学は,以前の理論的対立を解決する.
氷の月の液体の水が存在する可能性を裏付ける.

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