Mass-radius curve for extrasolar Earth-like planets and ocean planets
- Research areas:
- Year:
- 2007
- Authors:
- Journal:
- ICARUS
- Volume:
- 191
- Number:
- 1
- Pages:
- 337-351
- Month:
- NOV 1
- ISSN:
- 0019-1035
- BibTex:
- Abstract:
- By comparison with the Earth-like planets and the large icy satellites
of the Solar System, one can model the internal structure of extrasolar
planets. The input parameters are the composition of the star (Fe/Si and
Mg/Si), the Mg content of the mantle (Mg\#= Mg/{[}Mg+Fe]), the amount of
H(2)O and the total mass of the planet. Equation of State (EoS) of the
different materials that are likely to be present within such planets
have been obtained thanks to recent progress in high-pressure
experiments. They are used to compute the planetary radius as a function
of the total mass. Based on accretion models and data on planetary
differentiation, the internal structure is likely to consist of an
iron-rich core, a silicate mantle and an outer silicate crust resulting
from magma formation in the mantle. The amount of H(2)O and the surface
temperature control the possibility for these planets to harbor an
ocean. In preparation to the interpretation of the forthcoming data from
the CNES led CoRoT (Convection Rotation and Transit) mission and from
ground-based observations, this paper investigates the relationship
between radius and mass. If H(2)O is not an important component (less
than 0.1\%) of the total mass of the planet, then a relation
(R/R(Earth)) = a (M/M(Earth))(b) is calculated with (a, b) = (1, 0.306)
and (a, b) = (1, 0.274) for 10(-2) M(Earth)
