Speaker
Description
Low-mass exoplanets in a fully to partially molten state open a novel window into key processes that shape the earliest, high-temperature evolutionary regimes of rocky worlds and their long-lived climate states. I will outline how magma ocean dynamics and core-mantle chemical segregation influence the feedback mechanisms between largely molten interiors and volatile envelopes. The physical and chemical coupling between magma layers and their equilibrating atmospheres can fractionate the dominant volatiles observable in the upper atmosphere to a degree that is testable with current instrumentation. As a key example, nitrogen species can be suppressed in H-dominated atmospheres if the volatile envelope is in direct contact with a chemically reduced molten interior. With a focus on a few high-priority super-Earth and sub-Neptune exoplanets, I will outline observational tests to distinguish internal phase state and evolutionary scenarios.
