Houghton Lecture Series – Ray Pierrehumbert (University of Oxford)

Lava Planets

I will introduce this class of planets in ultra-short-period orbits, which are so hot they are
expected to have permanent surface magma oceans on the dayside. I will discuss the nature of
their possible atmospheres, and the physics governing vertical structure. One possible class of
atmospheres consists of mineral vapor evaporated from the magma ocean, which undergoes
a transonic flow towards the nightside, with pressure decreasing owing to condensation and
re-equilibration with the magma ocean as the atmosphere flows away from the substellar
point. Observational consequences of a thicker non-condensing background atmosphere are
discussed. There are several planned JWST observations of lava planets in Cycle I and Cycle II,
and I will discuss in particular the observational strategy for the lava planet K2-141b.

About this Series:
Supported by the Houghton Fund, Houghton Lecturers are distinguished visitors from outside MIT invited by the EAPS Program in Atmospheres, Oceans and Climate to spend a period of time, ranging from a week to several months, as scientists-in-residence within our Program. For more information and Zoom password please contact Kayla Bauer: kbauer@mit.edu