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Two planets merging by giant impact

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Detailed Description

Computer simulation of two planets undergoing a giant impact that results in a merger (accretion). The larger (target) body is one tenth the mass of the Earth and the smaller (impactor) body is 70% the mass of the target. The planets are colliding at 1.08 times their mutual escape velocity, which equates to 3.63 km/s. The collision angle, defined by the angle between the velocity vector at impact and the line of their centers of mass, is 30°. Off-axis collisions such as these are more probable than on-axis (head-on) collisions.

The top-left panel shows mantle and core materials as unique colors for the target and impactor. The top-right panel shows the density of material in kilograms per cubic meter. The bottom-left panel shows temperature in thousands of Kelvins. The bottom right panel shows pressure in Pascals.

Simulation run by T.S.J. Gabriel ( using SPLATCH, a planetary Smooth Particle Hydrodynamics code developed at the University of Bern (Reufer 2011), maintained by A. Emsenhuber (Ludwig Maximillian University of Munich; and H. Ballantyne (University of Bern;




Public Domain.


Citation: Gabriel & Cambioni (2023). The Role of Giant Impacts in Planet Formation, Annual Reviews.