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Updated: Jul 13, 2025

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一个行星碰撞后的光和由此产生的碎片云
Matthew Kenworthy1, Simon Lock2, Grant Kennedy3,4
1Leiden Observatory, Leiden University, Leiden, The Netherlands. kenworthy@strw.leidenuniv.nl.
Nature
|October 11, 2023
概括
在年轻的恒星周围可能会发生行星规模的巨大碰撞. 观测显示,一颗巨大的系外行星撞击后的恒星变得明亮,随后由由此产生的碎片云造成的日食.
科学领域:
- 太阳系外行星科学与天体物理学
- 恒星和原行星盘的演化.
背景情况:
- 在年轻恒星周围的尘埃状气体盘中形成行星.
- 在磁盘气体消散后,行星之间可能会发生巨大的撞击.
- 之前的斯皮策探测器发现了此类事件的红外发光.
研究的目的:
- 在年轻的恒星ASASSN-21qj周围调查一个独特的红外亮度事件.
- 确定所观察到的红外和光学变化的原因.
- 提供巨型系外行星碰撞的观测证据.
主要方法:
- 对恒星ASASSN-21qj的综合红外和光学观测
- 分析红外亮度,亮度和黑体温度.
- 红外照明和随后的光学日食的时间分析.
主要成果:
- 发现了持续约1000天的显著红外亮度 (1,000K,4%的恒星亮度).
- 一个复杂的,波长依赖的光学日食在2.5年后出现.
- 这一事件与两个系外行星 (几到几十个地球质量) 碰撞是一致的.
结论:
- 观测到的现象支持系外行星之间的巨大撞击场景.
- 红外辐射源于一个热的,扩展后撞击残留物.
- 光学日食是由冲击碎片的传递引起的.
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