Comet 67P formed in impact?

The unusual shape of comet 67P/Churyumov-Gerasimenko, as recorded by the Rosetta mission, has led to much speculation about its origins. A simulation published in March 2018 in Nature Astronomy suggests that the comet could have formed when two comets collided, and furthermore that such a collision even at quite high speeds would have left the constituent parts largely unaltered (no large rise in temperatures or pressures). This is important because it means that whenever Churyumov-Gerasimenko actually took its current shape, we can still draw conclusions about primordial material from the origins of the solar system using Rosetta results.

MiARD project