Planets Through Time: Understanding the Evolution and Diversity of Planetary Systems

穿越时间的行星：了解行星系统的演化和多样性

基本信息

批准号：
ST/W001047/1
负责人：
Edward Gillen
金额：
$ 33.88万
依托单位：
Queen Mary University of London
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2022
资助国家：
英国
起止时间：
2022 至无数据
项目状态：
未结题

来源：
https://gtr.ukri.org/projects?ref=ST%2FW001047%2F1
关键词：
Planets Through Time Understanding Evolution

项目摘要

With over 4000 exoplanets discovered to date, and many more expected in the coming years, we are living through a golden age of exoplanet discovery. We now know that planetary systems exhibit a wide diversity in their properties, and that our own Solar System is not typical. For example, we have found planets like Jupiter on orbits of only a few days (so called "hot Jupiters"), planetary systems containing multiple small planets on tightly packed orbits that are all smaller than Mercury's and, perhaps most surprising of all, we have discovered that planets with sizes between those of the Earth and Neptune are the most common, yet we have no such analogues in our own Solar System. The processes that govern how planetary systems develop into the diverse population that we observe are thought to occur during the first billion years after their formation. As known exoplanets typically orbit old stars like our Sun, which are more than a billion years old, it is difficult to unravel the processes that drove their early evolution as these processes have already finished. To understand the early evolution of planetary systems, we need to detect young planets, which are still in the processes of evolving; this is the aim of our programme. Transiting planets, whose orbital plane aligns with Earth so that they periodically pass in front of (i.e. transit) their host star, are the most valuable as they can be studied in greatest detail. We will search for young transiting planets in the combined dataset of two leading exoplanet surveys, the Next Generation Transit Survey (NGTS) and the Transiting Exoplanet Survey Satellite (TESS). The young planets that we detect will help us to understand the processes that drive the early evolution of planetary systems into the diverse population that we observe. They will also provide a link between (i) our theories of planet formation and early evolution and (ii) the known (old) exoplanet population. Furthermore, they will help us to understand some intrinsic properties of exoplanets themselves, such as why some hot Jupiters appear to be larger than we expect, and why there is a dearth of planets on short orbital periods that are just under twice the size of Earth.Finally, the majority of transiting planets detected to date are thought to have migrated from where they formed in towards their host star. Such significant migration did not occur in our Solar System. Ultimately, this work will help us to understand the observed diversity of transiting planet systems, as well as why the seemingly ubiquitous migration process did not progress in our Solar System.

迄今为止已发现了 4000 多颗系外行星，未来几年预计还会发现更多系外行星，我们正处于系外行星发现的黄金时代。我们现在知道行星系统在特性上表现出广泛的多样性，而我们自己的太阳系并不典型。例如，我们发现像木星这样的行星的轨道只有几天（所谓的“热木星”），行星系统包含多个小行星，这些小行星的轨道都比水星的紧密轨道小，也许最令人惊讶的是，我们已经发现，大小在地球和海王星之间的行星是最常见的，但我们自己的太阳系中没有类似的行星。我们认为，控制行星系统如何发展成为我们所观察到的多样化种群的过程被认为发生在其形成后的最初十亿年期间。由于已知的系外行星通常绕太阳这样的老恒星运行，这些恒星的年龄超过十亿年，因此很难解开驱动其早期演化的过程，因为这些过程已经完成。为了了解行星系统的早期演化，我们需要探测仍处于演化过程中的年轻行星；这是我们方案的目标。凌日行星的轨道平面与地球对齐，因此它们会定期经过（即凌日）其主恒星前方，因此它们是最有价值的，因为它们可以进行最详细的研究。我们将在两项领先的系外行星巡天——下一代凌日巡天（NGTS）和凌日系外行星巡天卫星（TESS）的组合数据集中寻找年轻的凌日行星。我们探测到的年轻行星将帮助我们了解推动行星系统早期演化为我们观察到的多样化种群的过程。它们还将提供（i）我们的行星形成和早期演化理论与（ii）已知（古老）系外行星种群之间的联系。此外，它们将帮助我们了解系外行星本身的一些内在特性，例如为什么一些热木星看起来比我们预期的要大，以及为什么缺乏轨道周期短且大小略低于地球两倍的行星最后，迄今为止发现的大多数凌日行星被认为是从它们形成的地方向它们的主恒星迁移的。在我们的太阳系中并没有发生如此重大的迁移。最终，这项工作将帮助我们了解观测到的凌日行星系统的多样性，以及为什么看似无处不在的迁移过程在我们的太阳系中没有取得进展。