在哈雷-波普彗星中确定了两种一氧化碳来源
M A DiSanti1, M J Mumma, N Dello Russo
1Department of Physics, The Catholic University of America, Washington, DC 20064, USA. disanti@kuiper.gsfc.nasa.gov
Nature
|June 29, 1999
概括
哈雷-波普彗星的彗星
科学领域:
- 天文学和天体物理学
- 行星科学 行星科学
- 天体化学是天体化学.
背景情况:
- 彗星冰的组成为太阳系形成提供了线索.
- 与水相对的一氧化碳 (CO) 丰富程度表明彗星前的材料加工.
- 之前在彗星冰中的CO测量是模两可的.
研究的目的:
- 为了确定彗星海尔-波普彗星冰中的本地CO2丰富度.
- 评估对前彗星材料的化学加工的影响.
- 要区分来自核的CO与昏迷的CO.
主要方法:
- 在Hale-Bopp彗星的现场观测.
- 与水冰相对的二氧化碳丰度的分析.
- 与分子云和原恒星外组成的比较.
主要成果:
- 大约50%的海尔波普彗星的CO2直接来自核冰.
- 冰中的二氧化碳与水的比率为12%,低于静止的分子云.
- 这一比例与原恒星外中发现的丰度一致.
结论:
- 黑尔-波普彗星中的冰块显示出在积累之前的加工证据.
- 观测到的二氧化碳丰度表明原恒星外中的形成条件.
- 在昏迷状态下进一步处理可能会导致剩余的CO.
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