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
IAU definition of planet devalue someone or something, as happened to the former planet Pluto when the General Assembly of the International Astronomical Union decided Pluto no longer met its definition of a planet." Society president Cleveland Evans stated the reason for the organization's selection of "plutoed": "Our members believe the great emotional reaction of the public to the demotion of Pluto shows the importance of Pluto as a name. We may no longer believe in the Roman god Pluto, but we still have a sense of connection with the former planet". IAU definition of planet The International Astronomical Union (IAU) defined in August