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从彗星67P/Churyumov-Gerasimenko的重力场来看,它的同质核

M Pätzold¹, T Andert², M Hahn¹

¹Rheinisches Institut für Umweltforschung an der Universität zu Köln, Abteilung Planetenforschung, 50931 Köln, Germany.

|February 5, 2016

概括

彗星67P/丘里乌莫夫-格拉西门科

科学领域:

星球科学
彗星科学
天体物理学

背景情况:

彗星核主要由尘埃和水冰组成.
之前的研究表明密度低,孔隙度高,但存在显著的不确定性.
对彗星核的准确描述对于了解太阳系形成至关重要.

研究的目的:

准确确定67P/Churyumov-Gerasimenko彗星核的质量,体积密度,孔隙性和内部结构.
改进我们对彗星组成和内部特性的理解.
调查核中的同质性和空隙存在.

主要方法:

在67P/Churyumov-Gerasimenko彗星的飞越过程中对航天器速度扰动的分析.
核的引力场和点质量的计算 (GM).
将重力数据与体积估计结合起来,以得出体积密度和多孔度.

主要成果:

确定了精确的质量 (M = (9,982 ± 3) × 10^9 kg) 和重力参数 (GM = 666.2 ± 0.2 m2/s2).
平均散体密度为533±6 kg/m3,表明密度低,体积较多孔 (72-74%).
据估计,尘埃的组成量大约是冰的四倍,体积是冰的两倍.
核内部被推断为均且没有大空隙.

结论:

彗星67P/Churyumov-Gerasimenko的核是一个高度多孔,低密度的物体,富含尘埃的组成.
内部结构在全球范围内看起来是均的,这表明性是一种固有的材料特性.
这些发现有助于更好地了解彗星内部及其形成过程.

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