多キロメートルの地球と火星を横断する小惑星の起源:定量シミュレーション
Migliorini1, Michel, Morbidelli
1F. Migliorini, Armagh Observatory, College Hill BT61 9DG, Northern Ireland, United Kingdom, and Osservatorio Astronomico di Torino, I-10025 Pino Torinese, Italy. P. Michel, Osservatorio Astronomico di Torino, I-10025 Pino Torinese, Italy, and Obse.
Science (New York, N.Y.)
|September 25, 1998
まとめ
弱い共鳴は,主帯の小惑星をゆっくりと火星を交差する軌道に押し込みます. その多くは地球を横断する小惑星になり,観測された集団を説明します.
科学分野:
- 惑星科学は惑星科学である.
- 軌道ダイナミクス 軌道ダイナミクス
- 小惑星研究研究.
背景:
- 主帯と近地空間における小惑星集団は,著しい関心を持っています.
- 小惑星のダイナミックな経路を理解することは,衝突の危険性評価に不可欠です.
研究 の 目的:
- 小惑星をメインベルトから火星横断軌道と地球横断軌道へと駆動するダイナミックメカニズムを調査する.
- 観測された火星横断小惑星 (MCAs) と地球横断小惑星 (ECAs) の数を定量的に説明する.
主な方法:
- 軌道ダイナミックシミュレーションを利用した.
- 小惑星の軌道要素に対する弱い平均運動共鳴の影響を分析した.
- 主帯から火星と地球を交差する軌道への小惑星の移行を追跡した.
主要な成果:
- 多くの弱い平均運動共鳴が,小惑星の軌道円性を徐々に増加させる.
- 小惑星は,メインベルトから火星を交差する軌道に効率的に駆動されます.
- 火星を通過する小惑星のおよそ50%が,2000万年以内に地球を通過する軌道に移行します.
結論:
- シミュレートされた軌道進化は,地球と火星を交差する大きな小惑星の観測された集団を定量的に説明します.
- 弱い共鳴は,主帯から発生した小惑星で近地空間を埋める上で重要な役割を果たします.
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