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Updated: May 22, 2026

11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
アステロイドベルトの不安定な延長からのアルカイアン時代の重爆撃
William F Bottke1, David Vokrouhlický, David Minton
1Southwest Research Institute and NASA Lunar Science Institute, 1050 Walnut Street, Suite 300, Boulder, Colorado 80302, USA. bottke@boulder.swri.edu
Nature
|April 27, 2012
まとめ
遅い重爆撃 (LHB) は,これまで考えられていたよりもはるかに遅れて,E帯から発生したインパクターで延長されました. この地域 この地域
科学分野:
- 惑星科学は惑星科学である.
- 天文学 天文学
- インパクトクラテリング (インパクトクラテリング)
背景:
- 後期の大爆撃期 (LHB) は,伝統的に約37~38億年前に終わったと考えられています.
- 証拠によると,地球上のLHBサイズの衝撃は,衝撃球状の床の形で,はるかに後で発生し,初期のプロテロゾイク時代まで続いた.
研究 の 目的:
- 後期の大爆撃の延長期間を調査する.
- 月面の盆地と地上の衝突球体床に起因する遅い衝撃の源を特定する.
主な方法:
- 地球に衝突した球状の床と月のクレーター記録の分析.
- 小惑星帯のダイナミクスと巨大惑星の移住のモデリング.
- 観測されたハンガリア小惑星からスケーリングして,衝撃波の流れを推定する.
主要な成果:
- LHBは,これまで考えられていたよりもずっと長く持続し,ほとんどの遅いインパクトはEベルトから発生した.
- Eベルト発射弾は37億~41億年前に約10の月面盆地を形成した.
- これらの衝突は17億年から37億年前の間に,数多くの陸地盆地とチクスルブサイズのクレーターも生み出した.
結論:
- 巨大な惑星の移住によって不安定になったE帯は,遅い衝突の重要な源でした.
- 拡張されたLHBは,Eベルトのオブジェクトによって駆動され,観測された衝突球状の床と月のクレーター発生率を説明します.
- この改訂された理解は,初期の太陽系爆撃の歴史についての私たちの見方を再構築します.
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