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Updated: Jun 23, 2026

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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
太阳风是小行星表面快速变红的来源
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
概括
由于太空气候变化,小行星的颜色迅速变化,在形成100万年内发生. 这种快速的过程,可能是由太阳风驱动的,表明小行星的颜色差异是由于组成,而不是年龄.
科学领域:
- 行星科学 行星科学
- 天文学 天文学
- 宇宙化学 宇宙化学
背景情况:
- 小行星看起来比石"更红",归因于太空气候变化,但它的机制和时间表仍在争论中.
- 以前的研究表明,年轻的小行星家族经历了最小的太空气候变化.
研究的目的:
- 为了研究太空气候对年轻小行星家族的时间尺度.
- 确定驱动空间气候变化的主要机制及其对构成的依赖.
主要方法:
- 将石的实验室反射谱与年轻小行星家族的观测数据进行了比较.
- 分析了小行星的颜色变化与它们的年龄和组成有关,特别是橄烯的丰富性.
主要成果:
- 太空气候变化是一个快速的过程,最终的小行星颜色是在重大碰撞后的106年内建立的.
- 由于其快速的实验速度,太阳风植入被认为是占主导地位的太空气候变化机制.
- 在实验室和小行星数据中,气候变化的有效性显示了对橄素丰富性的依赖.
结论:
- 快速的太空气候变化意味着小行星的颜色变化主要是由于组成或颗粒大小的差异,而不是年龄.
- 在行星碰撞期间的潮震动可能会使近地小行星的表面再生,解释它们的新鲜外观.
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