関連する実験動画
Updated: Jun 23, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
太陽風は小惑星の表面の急速な赤みが原因である
P Vernazza1, R P Binzel, A Rossi
1Research and Scientific Support Department, European Space Agency, Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands. pierre.vernazza@esa.int
Nature
|April 28, 2009
まとめ
小惑星の色は,宇宙気象による急速に変化し,形成から100万年以内に発生します. おそらく太陽風によって引き起こされるこの急速なプロセスは,小惑星の色の違いが年代ではなく組成によるものであることを示唆しています.
科学分野:
- 惑星科学は惑星科学である.
- 天文学 天文学
- 宇宙化学 (コスモケミストリー)
背景:
- 小惑星は隕石よりも"赤く"見えるが,これは宇宙気象に起因すると考えられているが,そのメカニズムと時間尺度については議論されている.
- 以前の研究では,若い小惑星ファミリーが最小限の宇宙気象を体験することを示唆しました.
研究 の 目的:
- 若い小惑星ファミリーの宇宙気象の時間スケールを調査するために.
- 空間気象を駆動する主なメカニズムと,その構成への依存を特定する.
主な方法:
- 隕石の実験室の反射スペクトルを,若い小惑星ファミリーの観測データと比較した.
- 分析された小惑星の色の変化は,その年齢と組成,特にオリビンの豊富さに関連しています.
主要な成果:
- 宇宙気象は急速なプロセスで,大衝突から10 ^ 6年以内に最終的な小惑星の色が確立されます.
- 太陽風の植え付けは,その急速な実験率のために,支配的な宇宙気象化メカニズムとして好まれている.
- 耐候効果は,実験室データと小惑星データの両方でオリビンの豊富さに依存していることを示しています.
結論:
- 急速な宇宙気象化は,小惑星の色の変動は,主に年代ではなく,組成または粒子の大きさによる違いによるものであることを示唆しています.
- 惑星との出会いの間における潮の揺れは,近地小惑星の表面を若返らせ,その新鮮な外観を説明するかもしれない.
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