Lava Lamps: A survey to search for silicate vapor atmospheres in the ultra-hot terrestrial planet population

Smith, Cole; Weiner Mansfield, Megan; Coy, Brandon; Bean, Jacob; Brady, Madison; Gao, Peter; Ih, Jegug; Kempton, Eliza; Kite, Edwin; Koll, Daniel; Luque, Rafael; Orell-Miquel, Jaume; Palle Bago, Enric; Piette, Anjali; Zhang, Michael
Bibliographical reference

AASTCS 11: Exoplanet Atmospheres 2026

Advertised on:
6
2026
Number of authors
15
IAC number of authors
1
Citations
0
Refereed citations
0
Description
Ultra-hot rocky exoplanets above 1700 K may possess dayside temperatures that are hot enough to have their surfaces vaporize and become a silicate vapor atmosphere. Secondary eclipse thermal emission can efficiently probe for the presence of these atmospheres on a rocky planet. We observed single JWST MIRI/LRS secondary eclipses for 10 ultra-hot rocky exoplanets and compared their computed dayside temperature with their expected temperature if they were a bare rock with no heat redistribution. We detect a trend in these planets with those with higher irradiation temperatures having a distinct drop in dayside temperature. With our current understanding of magma surfaces, this trend cannot be explained purely through surface composition and albedos. We are exploring other cooling mechanisms that could lower the day-side temperature like a silicate vapor atmosphere, a volatile rich atmosphere, and silicate vapor clouds.