Dartmouth Events

Abstract: The atmospheres of sub-Neptunes get moulded by the intense XUV flux radiating from the star, which results in mass loss from these exoplanetary atmospheres. This period of relentless irradiation from the host star lasts for around 100 million years post-formation, with an exponential decline hereafter. Light species, such as hydrogen and helium, are the most susceptible to this mass-loss mechanism. By observing exoplanets that are undergoing mass loss we can develop a deeper understanding of the mechanisms that cause it, and the timescales that they occur over. We are making use of HST’s STIS and VLT’s CRIRES+ to probe the escaping atmosphere of HIP94235b, a sub-Neptune class planet orbiting a 100Myr G-type star.