Neptune's mysterious, far-flung moon Nereid may be the last of the planet's original companions.

The moon count in our solar system just went up by three.

Astronomers have discovered 12 new moons around Jupiter, putting the total count at a record-breaking 92.

It now has 82 known moons; Jupiter has 79. It now has 82 known moons; Jupiter has 79. But 17 of the 20 have a retrograde orbit of Saturn, meaning they essentially orbit backwards from the planet and other moons. The retrograde moons were also likely part of a larger body, and their name are derived from Norse mythology. Gas, dust and collisions in outer spaceOne of the prograde moons has an angle of 36 degrees, similar to the other prograde moons close to Saturn named for Gallic mythology.