Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
Science. 2013 Dec 20;342(6165):1473-7. doi: 10.1126/science.1245450.
Determination of an exoplanet's mass is a key to understanding its basic properties, including its potential for supporting life. To date, mass constraints for exoplanets are predominantly based on radial velocity (RV) measurements, which are not suited for planets with low masses, large semimajor axes, or those orbiting faint or active stars. Here, we present a method to extract an exoplanet's mass solely from its transmission spectrum. We find good agreement between the mass retrieved for the hot Jupiter HD 189733b from transmission spectroscopy with that from RV measurements. Our method will be able to retrieve the masses of Earth-sized and super-Earth planets using data from future space telescopes that were initially designed for atmospheric characterization.
确定系外行星的质量是了解其基本性质的关键，包括其支持生命的潜力。迄今为止，系外行星的质量约束主要基于径向速度（RV）测量，但这些测量不适用于质量低、半长轴大或围绕暗弱或活动恒星运行的行星。在这里，我们提出了一种仅从传输光谱中提取系外行星质量的方法。我们发现，通过传输光谱法和 RV 测量法得到的热木星 HD 189733b 的质量之间存在很好的一致性。我们的方法将能够使用最初为大气特征描述而设计的未来空间望远镜的数据来检索地球大小和超级地球大小的行星的质量。
