In this episode, Dr. Luque delves into the fascinating realm of exoplanets and their composition. With the majority of known temperate exoplanets orbiting red dwarf stars, these celestial bodies present an intriguing field for exploration and research.

Dr. Luque and his colleague Pallé have been analyzing the masses and radii of these small transiting planets. Their research reveals three distinct populations - rocky, water-rich, and gas-rich. Contrary to the previously accepted bimodal radius distribution theory, which suggested atmospheric loss of a hydrogen/helium envelope, Dr. Luque proposes a new interpretation.

Their findings suggest a density gap that separates rocky exoplanets from water-rich ones. This division could shed light on the planets' formation, possibly linked to their location within their planetary systems before orbital migration. According to their model, rocky planets form within the snow line, while water-rich planets form outside it and later migrate inward.

Join us for an in-depth discussion with Dr. Luque as we delve into the intricacies of exoplanets, their formation, and the implications for our understanding of the universe.

Key Words: Exoplanets, Red Dwarf Stars, Planet Composition, Planet Formation, Orbital Migration, Density Gap.

Density, not radius, separates rocky and water-rich small planets orbiting M dwarf stars https://doi.org/10.1126/science.abl7164