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Updated: Jul 12, 2026

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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
160 Myr 前の小惑星の崩壊が,K/T 衝突器の発生源である可能性が高い
William F Bottke1, David Vokrouhlický, David Nesvorný
1Southwest Research Institute, 1050 Walnut St, Suite 300, Boulder, Colorado 80302, USA. bottke@boulder.swri.edu
Nature
|September 7, 2007
まとめ
隕石バプティスタナの1億6000万年前の破裂は,クレタセウス-第3期の大量絶滅を引き起こしたものを含め,隕石衝突の急増を引き起こした可能性がある.
科学分野:
- 惑星科学は惑星科学である.
- インパクトクラテリング (インパクトクラテリング)
- 小惑星のダイナミクス
背景:
- 長期にわたる地と月のクレーター形成率は,しばしば一定であると仮定されます.
- 証拠によると,過去1億年で,キロメートルの大きさの天体からの衝撃フルスが大幅に増加しています.
研究 の 目的:
- 最近の衝撃波の急増の原因を調査する.
- クレータ紀/三次紀の大量絶滅の原因となったチクスルーブ衝突体の起源を決定する.
主な方法:
- 衝撃フルースのデータの分析.
- 小惑星の断片のダイナミックモデリング.
- 小惑星破壊シミュレーション.
主要な成果:
- バプティスティナ小惑星の親体の壊滅的な破壊 (約. 直径170km) は,およそ1600万年前から存在していた.
- このイベントは,小惑星帯の内側に小惑星の断片を放出しました.
- これらの断片は,惑星を交差する軌道にゆっくりと送られてきた.
結論:
- バプティスティナ小惑星の降雨は,チクスルーブ衝突機の最も可能性の高い源 (>90%) である.
- この出来事は,おそらく白紀/三次紀の大量絶滅の出来事を引き起こした.
- この研究は,地質学的時間尺度における恒常的な衝撃率の仮定に異議を唱える.
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