エンケラドスのカッシーニの塵測定と,E環の起源への影響
Frank Spahn1, Jürgen Schmidt, Nicole Albers
1Institut für Physik, Universität Potsdam, Am Neuen Palais 10, Haus 19, D-14469 Potsdam, Germany.
Science (New York, N.Y.)
|March 11, 2006
まとめ
カッシーニ宇宙船のデータは,土星の衛星エンケラドスの周りのマイクロンサイズの塵粒子を明らかにした. この塵は,おそらくエンケラドスの地質学的に活発な南極地域から発生し,土星のE環に寄与しています.
科学分野:
- 惑星科学は惑星科学である.
- アストロジオロジー アストロジオロジー
- 宇宙物理学 宇宙物理学
背景:
- 土星のE環は,主に氷の粒子で構成された拡散した環です.
- 土星の衛星であるエンケラドスには地質学的活動の証拠があり,その中には羽根と暖かい南極地域が含まれています.
研究 の 目的:
- カッシーニミッションでエンケラドス周辺で検出された塵粒子の発生源を調査するためです.
- エンケラドスが土星のE環に大きく貢献しているかどうかを判断する.
主な方法:
- カッシーニ宇宙船の宇宙塵分析器 (CDA) からのデータの分析.
- 塵の衝突データと宇宙船の軌跡,その他のカッシーニの実験結果との相関.
主要な成果:
- ハイレート検出器は,ミクロンサイズの塵粒子の衝突がエンケラドスの近くでピークを記録し,最も近い接近に先立ちました.
- 非対称な塵の痕跡は,エンケラドスの南極圏で局所的な塵の発生を示唆している.
- 同時期のカッシーニのデータは,同じ地域における地質学的活動 (高表面温度,水ガス放出) を示した.
結論:
- エンケラドスは,月の周りに検出された塵の粒子の発生源である可能性が高い.
- エンケラドスの南極地域における地質学的プロセスが,塵の生成に起因している.
- エンケラドスは,土星のE環の主要な寄与者です.
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