バイナリー小惑星は,地球近辺の物体集団に含まれる.
J L Margot1, M C Nolan, L A M Benner
1California Institute of Technology, MC 150-21, Pasadena, CA 91125, USA. margot@gps.caltech.edu
まとめ
近地小惑星2000 DP107はバイナリー系で,スピンアップと核分裂によって形成された可能性が高い. これは,多くのより大きな小惑星がバイナリである可能性を示唆し,惑星防衛戦略に影響を与えます.
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
- 天体物理学 天体物理学
背景:
- バイナリー小惑星系は,小惑星の形成と進化を理解するために極めて重要です.
- 地球近傍小惑星 (NEAs) は,衝突の危険性を有しており,その特徴は惑星防衛に不可欠です.
研究 の 目的:
- 地球近傍小惑星2000 DP107.7の物理的および軌道特性を分析する.
- 二重小惑星系の形成メカニズムを調査する.
主な方法:
- レーダー画像を用いて,小惑星2000 DP107.7の大きさと構造を決定しました.
- 軌道のパラメータ (周期,半大軸) を分析して,システムの質量と密度を計算する.
主要な成果:
- 小惑星2000 DP107は,800mのプライマリと300mのセカンダリーで構成され,1.755日ごとに周回します.
- 計算された原発の散発密度は1.7 +/- 1.1 g/cm3で,強さのない体を示唆しています.
- 他のバイナリNEAでも同様の特徴が観察され,共通の形成経路を示しています.
結論:
- バイナリーNEAは,スピンアップと核分裂によって形成される可能性があり,おそらく,近い惑星との遭遇中に潮の混乱が原因です.
- 200m以上のNEAの約16%がバイナリーシステムであり,影響リスク評価に影響を与える可能性があります.
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