  Some parts of the accretion model of the jovian planets' formation are
studied in the context of Palatini gravity. We mainly focus on the critical
core mass, that is, a mass for which there is no hydrostatic equilibrium
solution for the planet's envelope, which is a starting point of the runaway
accretion. We also discuss the conditions needed to be satisfied by a planet
such that it can posses a massive gaseous envelope around a solid core.
