News Planetary Science Mars’ potato-shaped moons could be the remains of a shredded asteroid An upcoming mission will help determine how Phobos and Deimos formed Supercomputer simulations showed how an unlucky asteroid could be shredded as it passed close to Mars and eventually turn into a moon-forming ring of debris around the Red Planet. NASA, YouTube Share this:EmailFacebookTwitterPinterestPocketRedditPrint By Lisa Grossman November 20, 2024 at 1:33 pm Mars’ moons could be the remains of an ill-starred asteroid that got too close to the Red Planet.