Research Frontiers: Astrophysics

Thursday 02 February, 17:00 - 18:00
Blackett LT1

This event is now over.

This Research Frontiers is out of this world, (other worlds specifically) with Dr Subhanjoy Mohanty from the Astrophysics Group.

Snacks & Drinks as usual.

Talk title: Habitability of Terrestrial-Mass Planets around Red Dwarfs

The ubiquity of red dwarfs, combined with the relative ease of detecting terrestrial-mass planets around them, has made them prime targets for finding and characterizing planets in the "Habitable Zone" (HZ). However, it also appears that terrestrial-mass exoplanets are often born with voluminous H/He envelopes. If these planets retain such envelopes over Gyr time-scales, they will not actually be habitable, due to the greenhouse effect. Given the strong X-ray/UV fluxes of red dwarfs, we study whether sufficient envelope mass can be photoevaporated away for these planets to become habitable. We show that if a planet is born with such a thick atmosphere, only planets with very low masses (< Venus-mass) may eventually become habitable around red dwarfs. I will discuss the general implications of these results for habitability, and for the search for habitable planets to be undertaken by upcoming space missions such as TESS, CHEOPS and JWST.

Image credit: By ESO/M. Kornmesser - https://www.eso.org/public/images/eso1629a/, CC BY 4.0, Link