哈雷-波普彗星在很远的日中心距离上大量排放了CO的气体
Nature
|March 14, 1996
概括
海尔-波普彗星表现出异常的亮度是由于一氧化碳 (CO) 的排气,而不是水冰的升华. 这种二氧化碳升华正在从太阳很远的地方驱动其活动.
科学领域:
- 天文学 天文学
- 彗星科学 彗星科学
- 天体化学是天体化学.
背景情况:
- 发现的彗星C/1995 O1 (海尔波普) 在7AU处异常明亮.
- 彗星的亮度通常来自于由挥发性冰化驱动的尘埃粒反射.
- 在太阳附近常见的水冰升温在海尔波普目前的距离下不太可能发生.
研究的目的:
- 调查海尔波普彗星活动的源头在一个大的日中心距离.
- 确定负责彗星观测到的亮度和排气的挥发性物种.
主要方法:
- 探测了来自海尔波普彗星的二氧化碳排放.
- 搜索其他挥发性物种,但没有发现它们.
主要成果:
- 确认了海尔波普火山的二氧化碳排放量,这些排放量达到标志着大量排放的水平.
- 活动归因于一氧化碳升华,而不是水冰.
结论:
- 一氧化碳 (CO) 升华是海尔波普彗星在大日中心距离活动的主要驱动因素.
- 未来的观测可能会揭示彗星接近太阳时,其他挥发性物种的升华开始.
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