France, March 2 -- Project Id: 105568
Description: Objective
The initial conditions of the Earth and other terrestrial planets were set 4.5 Gy ago during their accretion from the solar nebula and their concomitant differentiation into an iron-rich core and a silicate mantle. Accretion in the solar system went through several different dynamical phases involving increasingly energetic and catastrophic impacts and collisions. The last phase of accretion, in which most of the Earth mass was accreted, involved extremely energetic collisions between already differentiated planetary embryos (1000 km size), which resulted in widespread melting and the formation of magma oceans in which metal and silicates segregated to form the core and mantle. ...