在Ryugu小行星的样本中,高贵气体和记录了其挥发性来源和最近的表面演变
Ryuji Okazaki1, Bernard Marty2, Henner Busemann3
1Department of Earth and Planetary Sciences, Kyushu University, Fukuoka 819-0395, Japan.
Science (New York, N.Y.)
|October 20, 2022
概括
对小行星Ryugu样本的分析揭示了太阳前和原始成分,为地球提供了洞察力
科学领域:
- 宇宙化学与行星科学
- 天体生物学与生命起源研究
- 太阳系的形成和演变
背景情况:
- 近地碳化小行星 (162173) 是与地球起源相关的挥发性化合物的潜在来源.
- 哈雅布萨2任务成功地从瑞古取出样本进行详细的实验室分析.
- 了解Ryugu的组成有助于破译早期地球的挥发物质.
研究的目的:
- 在Ryugu样本中分析贵重气体和同位素.
- 确定前太阳和原始元件的起源和结合机制.
- 调查古与碳状石,特别是CI石之间的关系.
主要方法:
- 在Ryugu样本中对贵重气体 (,,,,) 的同位素分析.
- 在样本中的各种宿主阶段对的同位素分析.
- 与已知的石群的同位素特征和元素丰度的比较.
主要成果:
- 瑞古样本主要由太阳前和原始成分组成,这表明太阳系早期的材料.
- 瑞古的高贵气体度超过了伊武纳型 (CI) 碳酸.
- 在不同样本阶段存在异分离的成分,支持与CI合体的联系.
- 银河系宇宙射线 (GCR) 暴露 (约500万年) 和太阳风植入的证据揭示了瑞古最近的辐射历史.
结论:
- 瑞古样本含有大量的太阳前物质和原始物质,提供了太阳系早期构成的直接证据.
- 同位素和元素数据强烈支持小行星Ryugu与CI的密切遗传关系.
- 这项研究阐明了瑞古在轨道迁移后通过GCR和太阳风相互作用的表面演变.
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