Series: Astronomy Colloquium
Date: Wednesday 29-Jan-2025
Time: 16:05-17:00 (4:05-5:00 pm)
Location: ATL 2400
Speaker: Dr. Shreyas Vissapragada (Carnegie Observatories)
Title: Observing Atmospheric Evolution in Extrasolar Planets
Atmospheric escape has driven the long-term evolution of most known planetary atmospheres, including terrestrial planet atmospheres in our Solar System. In this talk, I will discuss the wealth of information we can learn from studying atmospheric escape in extrasolar planets, focusing on three main observational efforts. I will first introduce The Unintentional NIRISS Escape Survey (TUNES), a JWST archival program aimed at automating detections of escaping helium using low-resolution NIRISS/SOSS data, which is providing unanticipated constraints on outflow morphology sculpted by star-planet interactions. Next, I will discuss a Magellan/WINERED survey to precisely constrain helium absorption in a sample of 50 sub-Neptunes, achieving population-level constraints on atmospheric escape in small planets. Finally, I will describe the Search for Transiting Exoplanets in Lyman-alpha (STELa): the largest HST program ever awarded to study exoplanets. With 625 orbits allocated over 3 years, STELa endeavors to measure absorption from escaping hydrogen in every nearby (<100 pc) system where it could possibly be observed. These three programs are part of a broader shift towards population-level constraints on exoplanet atmospheres.
In-person colloquia are usually preceded by espresso and ice cream at 1:45 pm outside room PSC 1150 and are followed by an informal reception at 5:15 pm in that room. Anyone interested in talking with the speaker, or being added to the colloquium announcement email list, should contact the colloquium organizer Dr. Richard Mushotzky. Lunch will normally be reserved for the speaker to talk to graduate students. Anyone asking a question during a talk is asked to raise their hand and be acknowledged before speaking. Contact Dr. Richard Mushotzky for details.
Colloquium Organizer:
Dr. Richard Mushotzky
Special accommodations for individuals with disabilities can be made by calling (301) 405-3001. It would be appreciated if we are notified at least one week in advance.