| Time：1110921 (Wed.) 14:20~16:20 Speaker：Prof.陳皜(Howard Chen) NASA Goddard Space Flight Center Title：Worlds Beyond: A Theoretical View of Extrasolar Planets in the Era of James Webb and Direct Imaging Missions Abstract：Rocky exoplanets are indicated to be common in the galaxy. Current and future instruments including the James Webb Space Telescope (JWST), high resolution ground-based spectrographs, and direct imaging missions for under consideration by the 2020 Decadal Survey on Astronomy and Astrophysics, promise to unveil the detailed nature of exoplanets orbiting G, K-, and M-stars. However, retrieval and interpretation of observational measurements will be challenging and require understanding of potential atmospheric compositions, star-planet environmental context, and their consequences on the planetary habitability and detectability of molecular spectral features. In this talk, I will highlight major results from my research in extrasolar planetary science, including the prediction of the “radius valley” in the Kepler planet sample, development of the first fully coupled 3D terrestrial chemistry-climate model, and explanation of the elemental ratio conundrum recently measured on pre-planetary materials. Our theoretical results, informed by observational measurements, have major ramifications for future efforts to characterize habitable exoplanets. For instance, we find that secular stellar flaring could highlight the existence of chemical compounds such as nitrous oxide (N2O) and nitric acid (HNO3), making these “beacons of life” highly amenable to future detection. As a future faculty member at Florida Tech, I will continue my research and teaching efforts in exoplanetary and space sciences, with the goal of finding life elsewhere and ultimately understanding the distribution of inhabited worlds around nearby and distant stars. Place：S101, Gongguan Campus, NTNU |
