【直播】【北大天文学术报告】戴飞：地外行星之最极端：熔岩行星、超蓬松行星与极轴轨道行星
直播二维码
本系列报告由北京大学科维理天文与天体物理研究所、北京大学天文学系主办，于2021年9月16日15:30开始，授权蔻享学术进行网络直播。
银地外行星之最极端：熔岩行星、超蓬松行星与极轴轨道行星
报告人
戴飞
时间
2021年9月16日 15:30
In order to understand a process as complex as planet formation, the most extreme cases are often the most revealing. At the hottest extreme of planet formation are the ultra-short-period planets (USP, orbital period ~1 day, <2 R_earth) which orbit their host stars just a few stellar radii away. Our uniform analysis of USPs revealed a prevalence of Earth-like rocky composition. The high mutual inclinations among USP planets also betray a dynamically hot formation scenario. Our upcoming JWST program will probe the surface mineralogy through phase curve variations on a 0.7 R_Earth USP. The “super-puffs” (planets with anomalously low density ~0.1 g cm^-3) are extremely susceptible to rapid hydrodynamic mass loss with a timescale that is much shorter than the system's age. Even more puzzling, super-puffs are estimated to have large scale heights of ~3000 km, yet recent observations revealed completely flat transmission spectra.
I will introduce a scenario that may explain these observations of “super-puff”. Finally, we will describe a few novel methods of measuring the orbital tilt of a planet. We found a population of Neptune-sized planets on polar orbits that might have initially formed further out in the disk before they dynamically arrived at their current close-in, misaligned orbits. The heat generated in the migration might have triggered an episode of intense atmospheric loss that is seen in the metastable He observation.
报告人介绍
图 | 戴飞
I was born in Nanjing, Jiangsu. I obtained my undergraduate degree in Natural Science at the University of Cambridge in 2014. I received my Ph.D in Physics from MIT in 2019. I have been a GPS Postdoc Fellow at Caltech since then.
北京大学科维理天文与天体物理研究所专题讲座直播&回放链接：
https://www.koushare.com/topicIndex/i/kiaa-pku
编辑：王茹茹
欢迎大家提供各类学术会议或学术报告信息，以便广大科研人员参与交流学习。