彗星シューメイカー・レヴィ9号が木星と衝突した波です

A P Ingersoll¹, H Kanamori

¹Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena 91125, USA.

Nature

|April 20, 1995

まとめ

彗星シューメイカー・レヴィ9号が木星に衝突し,大気波が観測された. ハッブル宇宙望遠鏡によって観測されたこれらの波は,深層衝突と木星の大気中の酸素と水素の大きな比率を示唆しています.

科学分野:

惑星科学は惑星科学である.
大気物理学大気物理学
彗星科学彗星科学

背景:

彗星シューメイカー・レヴィ9の断片が木星と衝突したことで,木星の深層大気を研究するユニークな機会が生まれました.
ハッブル宇宙望遠鏡の画像は,衝突地点から450m/sで最大2.5時間にわたって広がる円形のリングを捕捉しました.

研究の目的:

彗星が衝突した後に観測された大気変動の性質を調査する.
観測された波現象を説明する最も妥当な物理的メカニズムを決定する.

主な方法:

衝突後の木星の大気のハッブル宇宙望遠鏡の画像の分析.
3つの潜在的な波の干渉タイプのモデリング: 音波,平流層重力波,捕まった重力波.
モデル化された波の特性 (速度,振幅) と観測データを比較する.

主要な成果:

仮説化された熱帯圏の水雲の中の安定した層に閉じ込められた重力波だけが,観測された波の速度と振幅に一致しました.
このモデルは,深い衝撃と非常に安定したトラッピング層を必要とします.
この発見は,木星における酸素と水素の比率が潜在的に大きいことを示しており,もし湿ったコンベクションが安定した層を生成したならば,太陽比の約10倍である.

結論:

安定したトロポスフィアの層に閉じ込められた重力波は,観測された衝撃後の現象の最も可能性の高い説明です.
彗星の衝突は木星の大気圏に深く浸透した可能性が高い.
木星の大気の組成,特にO:H比は,太陽の豊富さから大きく異なる可能性があります.

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