Mars may have captured and split a comet to create its two moons

The two moons of Mars may once have been a single comet that was ensnared and split by the planet – and an upcoming mission could find out for certain.

How Mars got its two moons, Phobos and Deimos, is a bit of a mystery. They are small, 27 and 15 kilometres across respectively, and both orbit around the planet’s equator. Astronomers have suggested that they may have formed after a collision on Mars’s…