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Updated: Aug 9, 2026

11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
NEARの253マチルデのフライバイ:C型小惑星の画像
1J. Veverka, P. Thomas, A. Harch, B. Clark, J. F. Bell III, B. Carcich, J. Joseph, Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14853, USA. C. Chapman and W. Merline, Southwest Research Institute, 1050 Walnut Str.
まとめ
地球に近い小惑星の出会い (NEAR) 宇宙船
科学分野:
- 惑星科学は惑星科学である.
- 小惑星研究研究.
- 宇宙探査 宇宙探査
背景:
- 小惑星253マティルデ (Asteroid 253 Mathilde) は,巨大で,不規則で,大きなクレーターで覆われた近地小惑星である.
- 表面は暗く,アルベドはCM炭酸性コンドライトに似ている.
- 以前の研究では,その物理的性質に関する詳細なデータが欠けていました.
研究 の 目的:
- 小惑星253マチルドの物理的特徴を決定する.
- その内部構造と構成を調査する.
- マチルデを他の炭酸性コンドライト小惑星と比較するために.
主な方法:
- NEAR宇宙船が1997年6月27日の飛行中に撮った近距離画像.
- 表面アルベドと色彩のフォトメトリック分析.
- 画像データから体積を決定する.
- NEAR宇宙船のドップラー追跡を用いた質量推定.
主要な成果:
- 小惑星253マチルドは,およそ66x48x46kmの大きさです.
- 表面のアルベドは0.035から0.050の範囲で,検出された変動はありません.
- 平均密度は1.3 +/- 0.2 g/cm3として計算されました.
- この密度はCMコンドライトの約半分の密度です.
結論:
- 小惑星253マチルドは,非常に多孔性の高い内部構造を有しています.
- その低密度から,典型的なCM炭酸コンドライトとは異なる組成が示唆される.
- この発見は,近地小惑星の性質に関する重要な洞察を提供します.
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