Time-lapse video of Phobos in orbit around Mars (annotated and smoothed)

This time-lapse video captures a portion of the path that the moon Phobos takes around Mars. Over the course of 22 minutes, Hubble snapped 13 separate exposures of the little Martian moon.

The transitions between frames have been smoothed to illustrate continuous motion. Phobos completes an orbit in just 7 hours and 39 minutes, which is faster than Mars rotates. Rising in the Martian west, it runs three laps around the Red Planet in the course of one Martian day, which is about 24 hours and 40 minutes. It is the only natural satellite in the Solar System that circles its planet in a time shorter than the parent planet’s day.

Hubble photographed Phobos orbiting the Red Planet on 12 May 2016, when Mars was about 80 million kilometres from Earth. This was just a few days before the planet’s closest point to Earth in 11 years.