Series: Astronomy Colloquium
Date: Wednesday 15-Apr-2020
Time: 16:00-17:00 (4:00-5:00 pm)
Location: Online Zoom Only: Contact Eliza Kempton for URL
Speaker: Dr. Thaddeus Komacek (University of Chicago)
Title: Interpreting astronomical observations to characterize the atmospheric circulation, climate, and habitability of exoplanets
Over the past two decades, space-based observations with the Spitzer and Hubble space telescopes have allowed for detailed characterization of the atmospheric circulation of hot gas giant planets. The upcoming launch of JWST promises spectral characterization of the atmospheres of gas giant planets, along with a first glimpse at the atmospheres of terrestrial exoplanets in the habitable zones of M dwarf stars. In this talk, I will describe my research on theory and numerical simulations of the atmospheric circulation and climate of both hot gas giant exoplanets and temperate terrestrial exoplanets. First, I will show how light curves of transiting exoplanets taken over a full orbital phase can be used to understand their atmospheric circulation. I will discuss the observational differences between ultra-hot Jupiters and cooler gas giants, and describe theory for the mechanisms that impact the circulation of ultra-hot Jupiters. I will also present results from 3D general circulation modeling experiments that include the effects of hydrogen dissociation and recombination and compare these simulations to observations of KELT-9b, the hottest exoplanet discovered to date. Second, I will describe the effects of clouds on the climate and habitability of terrestrial exoplanets. I will show the effect of cloud coverage on the inner edge of the habitable zone for planets with varying radius and gravity orbiting late-type M dwarf stars. Additionally, I will show the effect of clouds on the detectability of water transmission features on terrestrial exoplanets orbiting late-type M dwarf stars with JWST. Finally, I will describe how LUVOIR/HabEx/OST promise to transform our understanding of the atmospheres of temperate terrestrial exoplanets.
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. 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.
Colloquium Organizer:
Prof. Richard Mushotzy
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.
