Like our moon, Deimos is tidally locked to Mars, meaning the same side always faces the planet—the only side visible to rovers on the Martian surface. The only way to see Deimos’ far side up close is for a probe like Hera to fly behind it, making such images more of a rarity.

For an hour, HERA flew as close as 5,600 kilometers from the Martian surface, at a speed of 33,480 kilometers an hour. It used the opportunity to test some of its scientific instruments, snapping around 600 pictures, including rare ones of Deimos.

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

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.

On the way to investigate the scene of a historic asteroid collision, a European spacecraft swung by Mars and captured rare images of the red planet's mysterious small moon Deimos, the European Space Agency (ESA) said Thursday.

Europe's HERA mission has taken a good look at Mars and its moon Deimos on its way to explore the aftermath of the DART impact in the Didymos–Dimorphos asteroid system.