气候变化领域集成服务门户(CCPortal): Exoplanet secondary atmosphere loss and revival

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DOI	10.1073/pnas.2006177117
	Exoplanet secondary atmosphere loss and revival
	Kite E.S.; Barnett M.N.
发表日期	2020
ISSN	0027-8424
起始页码	18264
结束页码	18271
卷号	117 期号:31
英文摘要	The next step on the path toward another Earth is to find atmospheres similar to those of Earth and Venus-high-molecularweight (secondary) atmospheres-on rocky exoplanets. Many rocky exoplanets are born with thick (>10 kbar) H2-dominated atmospheres but subsequently lose their H2; this process has no known Solar System analog. We study the consequences of early loss of a thick H2 atmosphere for subsequent occurrence of a high-molecularweight atmosphere using a simple model of atmosphere evolution (including atmosphere loss to space, magma ocean crystallization, and volcanic outgassing). We also calculate atmosphere survival for rocky worlds that start with no H2. Our results imply that most rocky exoplanets orbiting closer to their star than the habitable zone that were formed with thick H2-dominated atmospheres lack high-molecularweight atmospheres today. During early magma ocean crystallization, high-molecular-weight species usually do not form long-lived high-molecular-weight atmospheres; instead, they are lost to space alongside H2. This early volatile depletion also makes it more difficult for later volcanic outgassing to revive the atmosphere. However, atmospheres should persist on worlds that start with abundant volatiles (for example, water worlds). Our results imply that in order to find high-molecular-weight atmospheres on warm exoplanets orbiting M-stars, we should target worlds that formed H2-poor, that have anomalously large radii, or that orbit less active stars. © 2020 National Academy of Sciences. All rights reserved.
英文关键词	Atmospheric evolution; Exoplanets; Planetary science
语种	英语
scopus关键词	Article; astronomy; atmosphere; crystallization; mathematical model; molecular weight; priority journal; volcano
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160858
作者单位	Kite, E.S., Department of Geophysical Sciences, University of Chicago, Chicago, IL 60637, United States; Barnett, M.N., Department of Geophysical Sciences, University of Chicago, Chicago, IL 60637, United States
推荐引用方式 GB/T 7714	Kite E.S.,Barnett M.N.. Exoplanet secondary atmosphere loss and revival[J],2020,117(31).
APA	Kite E.S.,&Barnett M.N..(2020).Exoplanet secondary atmosphere loss and revival.Proceedings of the National Academy of Sciences of the United States of America,117(31).
MLA	Kite E.S.,et al."Exoplanet secondary atmosphere loss and revival".Proceedings of the National Academy of Sciences of the United States of America 117.31(2020).