Characterization of extrasolar planets using high-precision polarimetry

自从1995年在类太阳恒星51peg周围发现一颗行星以来，已经发现了近一千颗系外行星。有了开普勒太空望远镜，我们现在能够在其他恒星周围找到地球大小的世界。但我们怎么知道这些类地行星是否有适合我们生命繁衍的所有元素呢？偏振法是一种强大的系外行星表征方法，有一天可以回答这些问题，现在可以应用于巨型行星。一种创新的便携式偏振计将被开发出来，用于了解系外行星的大气成分。偏振法是一种很有前途的方法，它在未来可能是第一个可以探测太阳系外行星上液态水的方法。

Close to a thousand exoplanets have been found since the discovery of a planet around a Sun-like star, 51 Peg in 1995. With the Kepler space telescope, we are now capable of finding Earth-size worlds around other stars. But how do we know if these Earth-like planets have all the right ingredients for life like ours to flourish? Polarimetry is a powerful method of exoplanet characterisation that could one day answer such questions and can be applied, right now, to the giant planets. An innovative, portable polarimeter will be developed, that will be used to understand the atmospheric composition of exoplanets. Polarimetry is a promising method, which in the future may be the first method that can detect liquid water on extrasolar planets.