凝固力により,瓦堆積小惑星 (29075) 1950 DA の回転分解が防止される
Ben Rozitis1, Eric MacLennan1, Joshua P Emery1
1Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, Tennessee 37996, USA.
Nature
|August 15, 2014
まとめ
小さな小惑星は,重力だけでなく,凝固力によって一緒に保持されることがあります. この発見は,如何に瓦の山の小惑星が,これまで考えられていたよりも速く回転できるかを説明する.
科学分野:
- 惑星科学は惑星科学である.
- 天体物理学 天体物理学
- 地質学 地質学 地質学
背景:
- 小惑星は通常,固体ではなく,散らばった瓦の山です.
- 彼らの行動は,典型的には重力と摩擦によって説明されます.
- 凝固力は,小さな瓦の山にとって重要であると最近予測されました.
研究 の 目的:
- 小規模な瓦堆積小惑星における結束力の役割を調査する.
- 小惑星で観測された高速回転速度を説明してください.
- 小惑星 (29075) 1950 DA.の物理的振る舞いを分析する.
主な方法:
- 小惑星 (29075) 1950 DAの回転を分析した.
- 重力および凝結力による粒状物質の振る舞いのモデリング.
- 月面のレゴリットとの結合力の比較.
主要な成果:
- 小惑星 (29075) 1950 DAは重力と摩擦が許すよりも速く回転する瓦の山です.
- 構造的な故障を防ぐには,凝固力が必要である.
- これらの力の強さは,月面のレゴリトの強さに匹敵する.
結論:
- ヴァン・デル・ワールス力のような凝結力は,小さな瓦堆積小惑星の構造的整合性にとって極めて重要です.
- これらの力は,小さな小惑星の予想外の高速な回転速度を説明します.
- 凝固力に関するさらなる研究は,小惑星の行動のモデルを洗練することができます.
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