Invited comunication
B. Soares, V. Zh. Adibekyan
Abstract
Stellar atmospheres offer the only observational window into the remnants of planet-forming disk
composition, given that disks, with lifetimes typically lasting only a few million years, have long dis-
sipated around most discovered planet-hosting stars. When modeling the interiors of rocky planets
an one-to-one relation between the composition of the planet and the host stars is typically assumed.
However, Adibekyan et al (2021) showed that while there is a relation between the composition of
rocky planets and their host stars, the relation is not one-to-one. The study by Adibekyan et al.
(2021) has two potential limitations: i) The interiors of the planets were modeled assuming they are
made only of core and mantle, i.e., no volatiles, and ii) the present-day stellar abundances were used
as a proxy for the primordial protoplanetary disk composition. Some astrophysical
processes, such as atomic diffusion, can influence the stellar composition as the star
evolves. Thus, the present-day stellar abundances can be measurably different from their primordial
composition.
Over the last two years, we worked on the EXO-Terra project, which aimed at a comprehensive
analysis of the star-planet compositional link by overcoming the two aforementioned limitations.
Additionally, we increased the sample by about 50%. I propose an oral contribution to present the
final results of the EXO-Terra project.
Molecules and planets in the outer Galaxy: is there a boundary of the Galactic Habitable Zone?
Florence, Italy
2024 November
