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Updated: Jun 30, 2025

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至少十几颗恒星中的一颗有行星吞的证据
Fan Liu1,2,3, Yuan-Sen Ting4,5,6,7,8,9, David Yong4,5
1School of Physics and Astronomy, Monash University, Clayton, Victoria, Australia. fan.liu@monash.edu.
Nature
|March 21, 2024
概括
天文学家通过研究伴生对在恒星中检测到行星的痕迹. 这项研究揭示了至少七次行星吞食事件,
科学领域:
- 恒星天体物理学
- 外行星科学
- 天体化学
背景情况:
- 恒星的化学组成可以通过行星物质的摄入或行星形成过程而改变.
- 星球特征表现为元素丰度差异与尘埃凝结温度之间的相关性.
- 由于未知的发生率,小幅度和异构的恒星样本,检测这些特征是困难的.
研究的目的:
- 为了利用同生的恒星对来方便行星的探测.
- 通过使用高精度的化学丰度,在同产恒星的同质样本中识别行星特征.
- 通过观测数据来限制行星吞没,形成和演变的机制.
主要方法:
- 研究了91对具有明确选择功能的恒星.
- 对所选恒星样本获得的高精度化学丰度数据.
- 采用独立的贝叶斯指标来区分行星特征与原子扩散等其他因素.
主要成果:
- 在研究的同生恒星对中至少发现了7个行星吞食事件.
- 确定发生率为8%的行星吞.
- 我们成功地解开了星球特征的随机丰度变化和原子扩散.
结论:
- 提供了恒星化学组成中的行星签名的观测证据.
- 增加了对星球化学的理解.
- 提供了关于行星形成和吞没过程的关键观察约束.
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