隕石と近地小惑星の組成の違い
P Vernazza1, R P Binzel, C A Thomas
1Research and Scientific Support Department, European Space Agency, Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands. pierre.vernazza@esa.int
Nature
|August 16, 2008
まとめ
ほとんどの近地小惑星は,珍しいLLコンドライト隕石とスペクトル特性を共有しており,驚くべき起源を示唆しています. フローラ小惑星ファミリーは,輸送のためのヤルコフスキー効果の影響を受ける可能性のある主要な源である可能性があります.
科学分野:
- 惑星科学は惑星科学である.
- 天文学 (astronomy) 天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは,天文学 (astronomy) とは
- 宇宙化学 (コスモケミストリー)
背景:
- 地球近傍小惑星 (NEAs) と潜在的に危険な小惑星 (PHAs) の理解は,科学的および実用的な理由から極めて重要です.
- 小惑星の組成は,地球で見られる一般的な隕石の組成を反映すると予想されています.
研究 の 目的:
- NEAとPHAのスペクトル特性を調査する.
- 地球周辺の小惑星の起源と構成を決定する.
- NEAのための小惑星帯内の潜在的な源地域を特定する.
主な方法:
- 地球近傍小惑星のスペクトル分析.
- NEAのスペクトル特性を,既知の隕石クラスと比較した結果.
- 類似のスペクトル特性を持つ小惑星ファミリーを特定する.
主要な成果:
- PHAを含むほとんどのNEAは,LLコンドライト隕石に似たスペクトル特性を示しています.
- フローラ系小惑星は,類似のスペクトル特性を示し,NEAの発生源である可能性を示している.
- LLコンドライトのようなNEAの流行は,その希少性 (約. 隕石の落下の8%).
結論:
- 近地小惑星は主にFLORAファミリーに由来し,LLコンドライトとスペクトル的に類似しています.
- LLコンドライトのようなNEAの驚くべき豊富さは,ヤルコフスキー効果のようなサイズに依存する輸送メカニズムによって説明され得る.
- 主帯から地球周辺への小惑星輸送のダイナミクスを完全に理解するためには,さらなる研究が必要である.
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