February 9
Quantifying the impacts of tidal heating on small exoplanets
Dr. Mike Greklek-McKeon
Carnegie EPL
Abstract: Small planets between the size of Earth and Neptune are the most commonly detected planets in our galaxy, and great efforts have been made in recent years to understand their compositions, atmospheric conditions, and evolutionary histories. The properties of these small planets are often combined with information about the energy flux from the host star into the top of the planetary atmosphere to better understand the planet’s bulk composition and atmospheric evolution. But the planet’s interior composition and the energy flux into the base of the atmosphere is often completely unconstrained, yet it may represent a significant portion of the total planetary energy budget. Many of the best characterized small exoplanets are on close-in orbits with non-zero eccentricities, which leads to large tidal heat fluxes that can dramatically alter planet properties. I will discuss results from a combination of dynamical modeling and observational efforts to measure the eccentricities and tidal heat fluxes of small exoplanets, especially those targeted by JWST. These constraints lead to predicted volcanic outgassing for certain terrestrial planets, radius inflation and altered atmospheric chemistry for several sub-Neptunes, and prospects for observational constraints on the presence of liquid water and magma layers in rocky planets.
Host: Yoni Brande