论文标题
温带和干旱岩石系外行星的水蒸气检测前景
Prospects for water vapor detection in the atmospheres of temperate and arid rocky exoplanets around M-dwarf stars
论文作者
论文摘要
在温带岩石系外行星大气中检测水蒸气将是迈向表征系外行星宜居性的主要里程碑。过去的建模工作表明，使用James Webb空间望远镜（JWST），云形成可能会阻止地面海洋上的水蒸气检测到地面海洋。在这里，我们分析了在不同类别的靶标上H2O大气检测的潜力：干旱行星。使用过境光谱模拟，我们表明大气中的H2O可能更容易在表面上带有冷冰冰矿床的干旱行星上检测到，因为这样的行星将不具有限制光谱特征的过境深度的厚的H2O云甲板。但是，诸如带与二氧化碳和其他气体重叠之类的其他因素，矿物灰尘的灭绝，恒星和行星H2O线的重叠以及JWST可获得的最终噪声底线仍然带来重要的挑战。因此，将来，空间和地面光谱观测的结合对于可靠地检测到岩石系外行星上的H2O至关重要。
Detection of water vapor in the atmosphere of temperate rocky exoplanets would be a major milestone on the path towards characterization of exoplanet habitability. Past modeling work has shown that cloud formation may prevent the detection of water vapor on Earth-like planets with surface oceans using the James Webb Space Telescope (JWST). Here we analyze the potential for atmospheric detection of H2O on a different class of targets: arid planets. Using transit spectrum simulations, we show that atmospheric H2O may be easier to be detected on arid planets with cold-trapped ice deposits on the surface, because such planets will not possess thick H2O cloud decks that limit the transit depth of spectral features. However, additional factors such as band overlap with CO2 and other gases, extinction by mineral dust, overlap of stellar and planetary H2O lines, and the ultimate noise floor obtainable by JWST still pose important challenges. For this reason, combination of space- and ground-based spectroscopic observations will be essential for reliable detection of H2O on rocky exoplanets in the future.
