パン山とアトラス山の赤道上の山脊は,終端の積み重ねの装飾物である
Sébastien Charnoz1, André Brahic, Peter C Thomas
1Laboratoire AIM, Commissariat à l'Energie Atomique (CEA)/Université Paris 7/CNRS, 91191 Gif-sur-Yvette Cedex, France. charnoz@cea.fr
まとめ
土星の衛星であるパンとアトラスは,赤道に突出した山脊があるため,珍しい"空飛ぶ円盤"の形をしている. これらの山脊は,月が形成された後に蓄積されたリング粒子の巨大な堆積である可能性が高い.
科学分野:
- 惑星科学は惑星科学である.
- 土星のシステムダイナミクス
- リング・ムーン相互作用
背景:
- 土星の外側のメインリングは,強烈な潮力を経験し,蓄積に抵抗します.
- カッシーニミッションは,衛星パンとアトラスの珍しい"飛ぶ円盤"の形を明らかにした.
- これらの衛星は,典型的な天体形態学とは異なる,顕著な赤道上の山脊を有しています.
研究 の 目的:
- 土星の衛星パンとアトラスの突出した赤道上の山脊の形成を説明するために.
- リング粒子が小さな内蔵衛星に蓄積する過程を調査する.
- 観測された月の形態学と環環境のダイナミクスを調和させる.
主な方法:
- パンとアトラスの高解像度のカッシーニ宇宙船の画像の分析.
- 月の赤道と極の地形の特徴の比較.
- 衛星の表面にリング粒子の蓄積をモデル化.
主要な成果:
- カッシーニの画像は,パンとアトラスの荒れた極地と滑らかな赤道地形との明確な違いを明らかにしています.
- 赤道上の山脊は,蓄積されたリング材料と一致する特徴を示しています.
- 提案された山脊形成モデルは,観察された形態学的データと一致しています.
結論:
- パンとアトラスの赤道上の山頂は,巨大な"環粒子堆積"として解釈されています.
- これらの構造は,衛星形成とリングの平ら化後のリング物質の蓄積によって形成された可能性が高い.
- 斜面の形成は,月の周辺からリング物質が完全に除去される前に起こった.
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