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年轻的小行星家族作为石的主要来源
M Brož1, P Vernazza2, M Marsset3,4
1Charles University, Faculty of Mathematics and Physics, Institute of Astronomy, Prague, Czech Republic. mira@sirrah.troja.mff.cuni.cz.
Nature
|October 16, 2024
概括
大多数石来自最近的小行星破裂, 而不是古代的. 三个特定的小行星碰撞创造了年轻的家族,解释了地球上发现的H和L普通体的丰富性.
科学领域:
- 天文学
- 星球科学
- 宇宙化学
背景情况:
- 连接石与它们的母体是一个长期存在的天文挑战.
- 目前,只有大约6%的石落在月球,火星或小行星维斯塔等来源.
研究的目的:
- 确定大多数石落下的主要来源.
- 为了了解H和L的起源,
主要方法:
- 对小行星家族及其分离事件的分析.
- 检查石的宇宙射线暴露年龄.
- 研究石在大气层前的轨道分布.
- 与太阳系中观察到的尘埃带的相关性.
主要成果:
- 大约70%的石起源于最近的三次小行星崩 (5,8,7,6和<400万年前).
- 这些事件发生在Koronis和Massalia小行星家族中,创造了大量小碎片的年轻家族.
- 这些年轻的小行星家族暂时产生了比较老,更大的小行星家族更多的米尺寸碎片.
结论:
- 最近的小行星破裂是石的主要来源,特别是H和L普通石.
- 这些年轻小行星家族的独特特征解释了所观察到的石落分布.
- 这一发现显著提升了我们对小行星进化和石起源的理解.
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