Presentation 1 : Poster
EFFECT OF THE CHEMISTRY OF THE STELLAR NEBULA ON THE RELATIONSHIP BETWEEN MASS AND RADIUS OF SILICATE AND METAL RICH EXOPLANETS (PNP)
V. Dubois, A. Mocquet, C. Sotin
In the last ten years several tens of giant exoplanets have been discovered around stars of very
variable compositions. The inner structure of these planets is still unknown. Here, we look for
a general relationship between mass and radius, for known Earth like planets of the solar
system, and investigate how this relationship may be affected by the relative abundance of
elements such as Mg, Si, Fe, and S in the nebula where the planet accreted. Assuming that the
relative amount of the latter elements is similar to that in the star around which the planet
orbits. The equation of state of mineral physics are used to derive the radius of a planet from
its observed mass. A first step has been to check the model against the Solar system. A
good agreement is found not only for the determination of the mass, but also for the pressure
and gravity profiles provided by standard Earth's models.