期刊
ASTROPHYSICAL JOURNAL
卷 901, 期 2, 页码 -出版社
IOP PUBLISHING LTD
DOI: 10.3847/1538-4357/abacc3
关键词
Comet interiors; Cometary studies; Galactic cosmic rays; Comets; High-energy cosmic radiation; Cosmic rays
资金
- Solar-Terrestrial Centre of Excellence
- FNRS
- Living Breathing Planet project: NASA Astrobiology Institute [NNX15AE05G]
- NASA Exobiology grant [80NSSC17K0463]
- Swiss National Science Foundation (SNSF) [200020_182418]
- Swedish National Space Agency [108/18]
- Advanced Exploration Systems Division within the NASA Human Exploration and Operations Mission Directorate
- Belgian Science Policy Office [PRODEX/ROSINA PEA 90020, 2014-12-19]
- NASA [NNX15AE05G, 805157] Funding Source: Federal RePORTER
Since their formation in the protosolar nebula some similar to 4.5 billion years ago, comets are in storage in cold distant regions of the solar system, the Kuiper Belt/scattered disk or Oort Cloud. Therefore, they have been considered as mostly unaltered samples of the protosolar nebula. However, a significant dose of energy is deposited by galactic cosmic rays (GCRs) into the outermost tens of meters of cometary nuclei during their stay in the Oort Cloud or Kuiper Belt. We investigate the impact of energy deposition by GCRs on cometary nuclei. We use experimental results from laboratory experiments and the energy deposition by GCRs estimated by Gronoff et al. (2020), to discuss the depth down to which the cometary nucleus is altered by GCRs. We show that GCRs do not significantly change the isotopic composition of cometary material but modify the chemical composition and the ice structure in the outer layers of the nucleus, which cannot be considered as pristine solar nebula material. We discuss the effect of the collisional history of comets on the distribution of processed material inside the nucleus and its implication on the observation of comets.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据