What is the 'Space Potato' Spotted by NASA Mars Satellite? Explained

The Martian moon Phobos stands against the darkness of space. (Image Credit: NASA)

NASA recently shared a remarkable image on its Instagram page, featuring what they referred to as a "space potato." This captivating photo, however, is not of an actual potato but of Phobos, one of Mars' two natural moons. The image was captured using the High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter, which has been orbiting and studying Mars since 2006.

Phobos, named after the Greek god of fear, is significantly smaller than Earth's moon—about 157 times smaller. It is one of Mars' two moons, the other being the even smaller Deimos, named after the Greek god of dread. Scientists believe that Phobos and Deimos were once wandering rocks that Mars' gravitational pull captured, pulling them into its orbit. Recent analyses of Phobos' rough and reflective surface suggest that the moon might have originated from the asteroid belt between Mars and Jupiter and could have once been a comet.

The orbits of Phobos and Deimos are unstable. In tens of millions of years, scientists predict that Deimos will drift away into space, while Phobos will either break apart into a ring around Mars or crash into the planet's surface. Phobos is currently inching closer to Mars by about 6 feet (1.8 meters) every year. Despite this gradual approach, it will take approximately 50 million years for Phobos to collide with Mars or disintegrate.

This timeline provides ample opportunity for scientists to continue studying and admiring Phobos, whose distinctive features include streaks of white ice and the prominent Stickney Crater. This 6-mile (10-kilometer) indent is named after Chloe Angeline Stickney Hall, a mathematician and the wife of Asaph Hall, the discoverer of Mars' moons in 1877.