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太陽のオート雲を,その誕生星団の恒星から捉えた写真
Harold F Levison1, Martin J Duncan, Ramon Brasser
1Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302, USA. hal@boulder.swri.edu
Science (New York, N.Y.)
|June 12, 2010
まとめ
大半のオート雲彗星は,太陽ではなく他の恒星から発生した可能性が高い. 数学的シミュレーションによると,太陽はこれらの彗星を他の恒星の原惑星円盤から,誕生星群の初期の形成時に捕獲したことを示唆しています.
科学分野:
- 天文学 (astronomy) 天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは
- 惑星科学は惑星科学である.
- 天体物理学 天体物理学
背景:
- オート雲彗星は,太陽の前惑星円盤の中で形成されたと考えられています.
- これらの彗星は,巨大な惑星によって遠くの軌道に放出されました.
- 現在のモデルでは,観測されたオート雲の個体数を説明できない.
研究 の 目的:
- オート雲彗星の起源を調査する.
- オート雲の集団に関するモデルと観測の間の不一致に対処するために.
- 彗星の形成の代替メカニズムを探求する.
主な方法:
- 彗星の捕獲と放出の数値シミュレーション.
- 恒星の誕生群の中で太陽の形成をモデル化する.
- 若い太陽と他の星の原惑星円盤との相互作用を分析する.
主要な成果:
- 太陽は誕生星団の中で他の星から彗星を捕獲した.
- オート雲彗星の大部分は,外部原惑星円盤から発生している可能性がある.
- シミュレーションによると,彗星の90%以上は太陽系外で発生している可能性がある.
結論:
- 太陽の誕生クラスター環境は,オート雲の形成に重要な役割を果たした.
- オート雲彗星のかなりの部分は,星間起源である可能性が高い.
- この発見は,太陽系内でのみ彗星形成に関する伝統的な見解に異議を唱えている.
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