在Kudo-Fujikawa彗星的等离子尾部观察到的双电离碳
Matthew S Povich1, John C Raymond, Geraint H Jones
1Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA. mpovich@cfa.harvard.edu
Science (New York, N.Y.)
|December 13, 2003
概括
彗星C/2002 X5 (Kudo-Fujikawa) 揭示了一个独特的尾巴组成. 高碳离子丰度表明起源于尘埃中的有机耐火化合物,将彗星与太阳系材料联系起来.
科学领域:
- 天文学 天文学
- 行星科学 行星科学
- 彗星科学 彗星科学
背景情况:
- 彗星C/2002 X5 (Kudo-Fujikawa) 在0.19AU接近周日.
- 关于彗星组成和起源的先前研究.
研究的目的:
- 研究彗星C/2002 X5.5的组成.
- 确定彗星尾部观察到的离子的来源.
- 加强彗星与太阳系形成之间的联系.
主要方法:
- 使用太阳和日球天文台 (SOHO) 上的紫外线冠状图谱仪 (UVCS) 进行观测.
- 来自高分辨率光谱的彗星图像的重建.
- 对离子丰度的分析,特别是C+和C2+.
主要成果:
- 观测到一个半球状的中性云.
- 检测到C+和C2+离子的变量尾巴,这些离子断开并再生.
- 发现大量的C2+和C+ (与水相比≥24%).
结论:
- 高度的C+和C2+并非来自一氧化碳光解离.
- 碳离子可能源于彗星尘埃中的耐火有机化合物中原子碳的蒸发和光电离.
- 这一发现强化了彗星作为太阳系原始物质的载体的作用.
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