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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
昏迷中的化学处理是彗星HNC的来源.
W M Irvine1, E A Bergin, J E Dickens
1Five College Radio Astronomy Observatory, University of Massachusetts, Amherst 01003, USA. irvine@fcrao1.phast.umass.edu
Nature
|June 20, 1998
概括
彗星中的同化 (HNC) 可能是通过昏迷中的化学反应形成的,而不是来自保存的星际物质. 这一发现影响了我们如何解释彗星组成和太阳系早期条件.
科学领域:
- 天体化学是天体化学.
- 彗星科学 彗星科学
- 行星科学 行星科学
背景情况:
- 在Hyakutake彗星中发现的同化 (HNC),其丰富度与星际云相似,表明它可能是星际物质的幸存物质.
- 彗星中保存的星际物质可能会限制太阳系早期的过程.
- 另外,HNC可以在昏迷状态下通过光化学产生,限制其作为太阳系早期条件的直接指标的使用.
研究的目的:
- 为了调查HNC在彗星中的起源.
- 为了确定HNC是否代表保存的星际物质或是在彗星昏迷中产生的.
- 评估对理解早期太阳系构成的影响.
主要方法:
- 在哈雷波普彗星中分析HNC/HCN比率.
- 观察到的HNC/HCN比率与化学模型的预测进行比较.
- 区分彗星核起源与现场昏迷产生之间的区别.
主要成果:
- 黑尔-波普彗星中的HNC/HCN比率显示,随着日中心距离的变化.
- 这种观察到的变化与昏迷中HNC的气相化学生产模型一致.
- 数据不支持直接来自彗星核的HNC.
结论:
- HNC主要是通过彗星昏迷中发生的化学反应形成的.
- 昏迷中的光化学过程是观察到的HNC的主要来源.
- 彗星HNC的丰富性不应该直接解释为保存的星际物质;必须考虑彗星化学.
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