Natural satellite been directly observed, have been called "moonlets". Small asteroid moons (natural satellites of asteroids), such as Dactyl, have also been called moonlets. The upper limit is also vague. Two orbiting bodies are sometimes described as a double planet rather than primary and satellite. Asteroids such as 90 Antiope are considered double asteroids, but they have not forced a clear definition of what constitutes a moon. Some authors consider the Pluto–Charon system to be a double (dwarf) planet. The most common dividing line on what is considered a moon rests upon whether the barycentre is below the surface of the larger
The Adventures of Pluto Nash become stranded on the Moon and desires to earn some money by which to pay for transport back to Earth to Salt Lake City. Because her father "Nicky Sticks" was a friend of Pluto's, she seeks help from Pluto, offering her skills as a singer. Pluto instead gives her a job as a server at his club and allows her to remain inside to sleep after its nightly closure to the public. During the same night, Pluto is accosted thrice by Mogan (Joe Pantoliano) and Kelp (Victor Varnado), messengers of a mysterious entrepreneur called Rex Crater. They tell Pluto that