The evolution of Venus: Present state of knowledge and future exploration
The evolution of Venus: Present state of knowledge and future exploration
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DOI：
10.1016/j.pss.2011.04.007
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发表时间：
2012-04-01
影响因子：
2.4
通讯作者：
Leblanc, Francois
中科院分区：
文献类型：
--
作者：
Chassefiere, Eric;Wieler, Rainer;Leblanc, Francois
金星形成和演化的详细描述是研究类地行星及其不同演化的关键环节。虽然地球和较小程度上的火星（由于对 SNC 陨石的分析）在比较行星学背景下得到了广泛的研究，但太阳系中最像地球的行星金星的历史仍然知之甚少。金星处于目前的极端气候状态多久了？它何时以及如何偏离（可能的）早期类地状态？金星在其早期历史的某个时期是否是一颗潜在的宜居行星？在吸积结束和后期猛烈轰击之间是否发生了“金星早期冷”阶段，就像地球所怀疑的那样？金星/地球的比较对整个宇宙中宜居类地行星的性质和演化有何影响？我们对金星气候演化的理解中一个主要的观测缺失环节是金星大气中稀有气体和稳定同位素的元素和同位素模式，但人们仍然知之甚少。重惰性气体（Kr、Xe）及其同位素的浓度大多是未知的，我们对轻惰性气体和稳定同位素的了解是不完整和不准确的。在本文中，我们总结了目前对金星早期演化的理解，包括了解水是否曾在行星表面凝结的关键问题。然后，我们评估了惰性气体、其同位素和稳定同位素的精确测量对增进我们对金星演化的理解的潜在贡献，并列出了惰性气体和同位素测量将有助于回答的主要问题。最后，我们展示了未来对金星的探索如何能够通过基于单个气球探测器的小型现场任务来了解金星的早期演化，该探测器被称为 EVE（欧洲金星探测器），该探测器是在欧空局宇宙愿景计划的框架内提出的。 (C) 2011 Elsevier Ltd. 保留所有权利。
A detailed characterization of the formation and evolution of Venus is a key link to the study of terrestrial planets, and to their divergent evolutions. While Earth and to a lesser extent Mars (thanks to the analysis of SNC meteorites) are extensively studied in a comparative planetology context, the history of the most Earth-like planet of the Solar System, Venus, is still poorly understood. For how long has Venus been in its current extreme climate state? When and how did it diverge from a (possible) early Earth-like state? Has Venus been a potentially habitable planet at some time of its early history? Did a "cool early Venus" stage occur between the end of accretion and the late heavy bombardment, like suspected for Earth? What are the implications of the Venus/Earth comparison for the nature and evolution of habitable terrestrial planets throughout the universe? A major observational missing link in our understanding of Venus' climate evolution is the elementary and isotopic pattern of noble gases and of stable isotopes in Venus' atmosphere, still poorly known. The concentrations of heavy noble gases (Kr, Xe) and their isotopes are mostly unknown, and our knowledge of light noble gases and stable isotopes is incomplete and inaccurate. In this paper, we summarize our present understanding of Venus' early evolution, including the crucial question of knowing if water ever condensed at the surface of the planet. Then, we assess the potential contribution of a precise measurement of noble gases, their isotopes and stable isotopes to improve of our understanding of Venus evolution, and list the main questions that noble gases and isotope measurements would help to answer. Finally, we show how future exploration of Venus could allow to gain a glimpse into the early evolution of Venus through a small in-situ mission based on a single balloon probe, called EVE (European Venus Explorer), proposed in the frame of the ESA Cosmic Vision program. (C) 2011 Elsevier Ltd. All rights reserved.