在碎片化彗星73P/Schwassmann-Wachmann 3中构成的一致性
N Dello Russo1, R J Vervack, H A Weaver
1Space Department, The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, Maryland 20723-6099, USA. neil.dello.russo@jhuapl.edu
Nature
|July 13, 2007
概括
在73P/Schwassmann-Wachmann 3的碎片中研究的彗星冰的组成显示出令人惊的统一性. 这表明彗星中观察到的碳链化学是原始的,而不是太阳进化的结果.
科学领域:
- 彗星科学是一门彗星科学.
- 天体化学是天体化学.
- 太阳系的形成太阳系的形成
背景情况:
- 彗星挥发性冰的组成有很大的变化,受形成环境,储存和太阳能处理的影响.
- 要了解这种多样性,需要深入分析彗星核的化学成分.
- 以前的观察在评估形成条件和进化效应方面是有限的.
研究的目的:
- 为了研究73P/施瓦斯曼-瓦赫曼3号彗星的不同碎片的化学成分.
- 评估形成条件与进化过程在彗星冰组成中的作用.
- 为了确定短周期彗星中是否存在与深度的组成变化.
主要方法:
- 对彗星73P/施瓦斯曼-瓦赫曼3的两个独立碎片的化学组成进行分析.
- 碎片组成相互比较以及与更广泛的彗星群体进行比较.
- 与已知的彗星水库相比,对挥发性冰的消耗进行评估.
主要成果:
- 73P/Schwassmann-Wachmann 3的两个碎片表现出非常相似的化学组成.
- 这种统一性与短期彗星中预期的组成多样性形成鲜明对比.
- 与其他彗星相比,彗星73P/Schwassmann-Wachmann 3 的极易挥发的冰层已经耗尽.
结论:
- 73P/Schwassmann-Wachmann 3碎片的均组成挑战了对短周期彗星进化处理的预期.
- 观察到的挥发性冰和碳链化学物质的减少表明原始起源,而不是进化.
- 彗星冰的组成可能比以前认为的更能反映出最初的形成条件.
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