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Dix Planetary Science Seminar

Tuesday, January 14, 2020
4:00pm to 5:00pm
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South Mudd 365
Stellar Flares and Habitable (?) M-dwarf Worlds with TESS
Max Gunther, Postdoc, MIT,

Abstract: Finding and characterizing small exoplanets transiting small stars naturally poses the question of their habitability. A major contributing factor to this might be stellar flares, originating from powerful magnetic reconnection events on the star. While too powerful flaring can erode or sterilize exoplanets' atmospheres and diminish their habitability, a minimum flare frequency and energy might be required for the genesis of life around M-dwarfs in first place. Here, I will first highlight our TESS study of stellar flares and our search for exoplanets transiting these stars, linking our findings to prebiotic chemistry and ozone sterilization. We already identified thousands of flaring stars, including many young, rapidly rotating M-dwarfs, some showing superflares with over 30x brightness increase in white light. Further, I will discuss a particularly interesting, newly discovered system: a super-Earth and two sub-Neptunes transiting the bright and nearby M-dwarf TOI-270, which is optimally suited to study the 'missing link' between planets on either side of the radius gap. With upcoming TESS sectors, stellar flare studies and new exoplanet discoveries will ultimately aid in defining criteria for exoplanet habitability.

For more information, please contact Shreyas Vissapragada by email at svissapr@caltech.edu.