Shoemakerクレーターは,小惑星433 Erosのほとんどの噴出ブロックの源泉である
P C Thomas1, J Veverka, M S Robinson
1Center for Radiophysics and Space Research, Cornell University, Ithaca, New York 14853, USA. thomas@cuspif.astro.cornell.edu
Nature
|September 28, 2001
まとめ
小惑星433 エロス
科学分野:
- 惑星科学は惑星科学である.
- 小惑星の表面プロセス
- インパクトクラテリング (インパクトクラテリング)
背景:
- 小惑星のレゴリティは,主に衝突噴出物です.
- 解像度が限られているため,クレーター源の特定とレゴリット研究が困難です.
研究 の 目的:
- 高解像度画像を用いて,小惑星433エロス (Eros) を世界的にマッピングする.
- 噴出源を特定し,レゴリット変化を分析する.
主な方法:
- 小惑星433エロス (Eros) の地球地図作成
- NEAR-Shoemaker宇宙船からの高解像度の画像の分析.
- エジェクタ置換モデルの適用.
主要な成果:
- エロスのほとんどの大きな噴出ブロックは,おそらく7.6kmの若いクレーターから発生しています.
- 古いエジェクタは,埋もれたり浸食されたように見える.
- 証拠は,レゴリット粒子の堆積後の分類環境を示唆しています.
結論:
- 最近の大規模な衝突がエロスの表面を大きく変形させた.
- エロスのレゴリスは,複雑な改変プロセスを経てきました.
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