A giant impact: Solving the mystery of how Mars' moons formed

Where did the two natural satellites of Mars, Phobos and Deimos, come from? For a long time, their shape suggested that they were asteroids captured by Mars. However, the shape and course of their orbits contradict this hypothesis. Two independent and complementary studies provide an answer to this question. One of these studies, to be published in The Astrophysical Journal and predominantly conducted by researchers from the CNRS and Aix-Marseille Universite, rules out the capture of asteroids, ...