Université de Montréal

Published purpose

This project will observe the thermal emission of TOI-849 b, one of the most intriguing sub Neptunes, with JWST. Because of its large mass and its high temperature, TOI-849b is an ultra-dense and ultra-hot sub-Neptune which is thought to be the exposed remnant core of a giant planet, akin to the deep interior of our own Jupiter but without the extended hydrogen atmosphere. These observations will characterize the composition and structure of the planet and reveal key insights into its nature and evolution. This will represent a major step for sub-Neptune and planet formation science by giving a previously unobtainable direct look at a planetary core of a giant planet, enabling abundance and temperature structure measurements.