The formation and detectability of exomoons

太阳系中所有较大的行星都有天然卫星。特别是这些由冰和气体组成的巨行星，拥有超过200颗卫星，甚至质量较小的天体，如矮行星，也有伴星围绕其运行。从太阳系可以推断，卫星是系外行星周围的太阳系外系统中常见的物体。讨论了几种形成通道：捕获形成卫星，巨大的冲击形成，以及在环行星盘中凝聚形成系外卫星。迄今为止，人类已发现了2600多个系外行星系统，其中包含4000多颗行星，其中以轨道周期小于100天的超级地球（1-20个地球质量的行星）数量最多，其次是距中心星星1-3个天文单位的巨行星。 然而，直到今天，还没有确认探测到系外卫星，主要是由于当前一代望远镜的灵敏度几乎足以探测到大质量系外行星周围的大质量系外卫星。在手头的这个提议中，我们打算研究巨大的撞击冰和气体巨星形成的系外卫星。

All larger planets in the Solar System have natural satellites. Especially the ice and gas giants harbour together over 200 moons, and even less massive objects like dwarf planets are orbited by companions. From the Solar System one might deduce that moons are common objects in extrasolar systems around exoplanets. Several formation channels are diskussed: the formation of moons by capture, the formation by giant impacts, and the formation of exomoons by agglomeration in a circumplanetary disk. Up to the present, over 2600 exoplanetary systems that contain over 4000 planets have been diskovered.The observations show that the most abundant planets are super-Earths (planets with 1-20 Earth masses) with orbital periods shorter than 100 days, followed by giant planets at distances of 1-3 astronomical units from their central star. However, there is no confirmed detection of an exomoon until the present day, mostly due to the current generation telescope sensitivity which is almost sufficient to detect massive exomoons around massive exoplanets. In this proposal at hand, we intend to study the formation of exomoons by giant impacts on ice and gas giants.