Yes, asteroids can have moons! Some of the larger asteroids in our Solar System actually do have moons. In 1993, a tiny moon called Dactyl was discovered orbiting the large asteroid Ida. Dactyl is only about 1 mile wide, while Ida is about 19 miles across. Since then, several other moons have been discovered orbiting asteroids. In 1999, an 8 mile wide moon called Petit-Prince was discovered orbiting the 135 mile wide asteroid Eugenia. In 2000, the 90 mile wide asteroid Pulcova was discovered to have its own moon, about nine miles wide. Over two dozen more have been discovered.
The first asteroid moon was discovered in pictures that were snapped 25 years ago today. The Galileo spacecraft was passing through the asteroid belt on its way to Jupiter. It flew close to Ida, an asteroid that’s about 35 miles long. When mission scientists looked at the pictures of Ida a few days later, they discovered a mile-wide companion. They named it Dactyl, after creatures from Greek mythology that lived on Mount Ida.
The most likely way for an asteroid to get a moon is through a collision with another asteroid. If the impact is at the right speed and angle, it can chip off a chunk of rock and send it into orbit. If the impact is too strong, though, the debris sails away into space, leaving the parent asteroid behind.
Picture Credit : Google