原始的な超海王星の天体による小惑星帯の汚染
Harold F Levison1, William F Bottke, Matthieu Gounelle
1[1] Southwest Research Institute, 1050 Walnut Street, Suite 300, [2] Center for Lunar Origin & Evolution, NASA Lunar Science Institute, Boulder, Colorado 80302, USA.
Nature
|July 17, 2009
まとめ
巨大な惑星の移住は,原始的な物体を小惑星帯に挿入し,その多様な構成を説明しました. これらの捕獲された体は,原始的な微小隕石の主要な源である.
科学分野:
- 惑星科学は惑星科学である.
- 天文学 天文学
- 天体物理学 天体物理学
背景:
- 主要な小惑星帯には,氷岩から岩火岩まで多様な物体が展示されています.
- 現在のモデルによると,小惑星は化学的に多様化した原始円盤の中で"in situ"で形成された.
研究 の 目的:
- 小惑星帯の多様性の起源を調査するために.
- 巨大惑星の軌道ダイナミクスが小惑星の組成に及ぼす影響をテストするために.
主な方法:
- ニースモデルを用いて巨大惑星の軌道の動的進化をシミュレートした.
- 超海王星の天体が外側の小惑星帯に挿入された経緯を追跡した.
主要な成果:
- ニース・モデルの巨大惑星移動は,原始的な超海王星の天体を外側の小惑星帯に挿入する.
- これは,原惑星円盤の内在的な組成の変化を必要とせずに,観測された多様性を説明します.
- 捕獲された,有機に富んだ体は,マイクロ隕石の集団に大きく貢献し,それらの原始的で同位体的に独特な性質を説明します.
結論:
- 小惑星帯の多様性は,外部からの物質供給によって大きく影響を受けます.
- 巨大な惑星のダイナミクスは,太陽系内部の天体の組成を形作る上で重要な役割を果たします.
- 原始的な隕石の起源は,捕獲された超海王星の天体と関連しています.
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