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Two planets undergoing a hit-and-run impact

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Detailed Description

Computer simulation of two planets undergoing a hit-and-run giant impact. This style of collision comprises around half of the giant impacts expected to occur during the latter stages of Solar System formation. The larger (target) body is one tenth the mass of the Earth and the smaller (impactor) body is 70% the mass of the target. When the impactor survives relatively intact after the collision, it is sometimes referred to as the runner. The planets are colliding at 2.5 times their mutual escape velocity, which equates to 8.40 km/s. The collision angle, defined by the angle between the velocity vector at impact and the line of their centers of mass, is 60°.

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.