A Study of the Accuracy of Mass-Radius Relationships for Silicate-Rich and Ice-Rich Planets up to 100 Earth Masses

Understand

A mass-radius relationship is proposed for solid planets and solid cores ranging from 1 to 100 Earth-mass planets.

• It relies on the assumption that solid spheres are composed of iron and silicates, around which a variable amount of water is added.
• The M-R law has been set up assuming that the planetary composition is similar to the averaged composition for silicates and iron obtained from the major elements ratio of 94 stars hosting exoplanets.
• Except on Earth for which a tremendous amount of data is available, the composition of silicate mantles and metallic cores cannot be constrained.