The results of Hera's fly-by could ultimately tell us whether Deimos is a captured asteroid or made from debris from a giant impact on Mars.

While the car-sized spacecraft flew around the Mars system, flight controllers on Earth temporarily lost communication with Hera because the signal was blocked. Though the blackout was planned for the maneuver, Ian Carnelli, the European Space Agency's Hera mission manager, said it was deeply emotional.

A mission to survey the results of a deliberate crash between an asteroid and a NASA spacecraft has taken stunning images of Mars and its moon Deimos