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Updated: Jun 30, 2026
11:20
Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
惑星衝突機の起源は太陽系内部の太陽系にある
Robert G Strom1, Renu Malhotra, Takashi Ito
1Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA.
Science (New York, N.Y.)
|September 17, 2005
まとめ
内部惑星への古代小惑星の衝突は,太陽系の歴史に関する手がかりを明らかにします. これらの古代の衝突星の大きさの分布は,主帯小惑星ではなく,近地小惑星と密接に一致しています.
科学分野:
- 惑星科学は惑星科学である.
- 太陽系の進化 太陽系の進化
- インパクトクレーター研究
背景:
- 太陽系内部の歴史は,月,火星,金星,水星のような地上の惑星の衝突クレーターに記録されています.
- 小惑星集団は,太陽系の進化に関するさらなるデータを提供します.
- 大量の爆撃が起こった時期は,およそ38億年前でした.
研究 の 目的:
- 衝突クレーター記録を通して,太陽系内部の歴史を理解する.
- 小惑星集団の大きさの分布と,古代の衝突物との関係を分析する.
主な方法:
- 月,火星,金星,水星の衝突クレーター記録の分析.
- 主帯小惑星と近地小惑星を含む小惑星集団のサイズ分布の調査.
主要な成果:
- 重い爆撃期 (約38億年前に終わった) のクレーターは,主小惑星帯から放出された小惑星によって形成されました.
- この古代時代の衝突機の大きさの分布は,主帯小惑星と大きく異なる.
- これらの古代の衝突惑星の大きさの分布は,近地小惑星の大きさの分布と非常に似ています.
結論:
- 巨大惑星の軌道移動は,主帯から動的に小惑星を放出した可能性があります.
- 近地小惑星は,初期の太陽系の重爆撃段階からの衝突物体の残骸または子孫を表す可能性があります.
- 衝突記録と小惑星集団の研究は,太陽系内部のダイナミックな歴史に関する重要な洞察を提供します.
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