Moons of Pluto meters per pixel were returned of Nix and up to 1.1 kilometers per pixel of Hydra. Lower-resolution images were returned of Styx and Kerberos. Author Edmond Hamilton referred to three moons of Pluto in his 1940 novel "Calling Captain Future", naming them , , and . Charon was listed as the largest of them. All three moons would not be discovered until the year 1970, according to Hamilton. The real Charon was discovered in 1978. Moons of Pluto The dwarf planet Pluto has five moons down to a detection limit of about 1 km in diameter. In order of distance
Naming of moons is the latter's number in parentheses. Thus, Dactyl, the moon of 243 Ida, was at first designated "S/1993 (243) 1". Once confirmed and named, it became (243) Ida I Dactyl. Similarly, the fourth satellite of Pluto, Kerberos, discovered after Pluto was categorized as a dwarf planet and assigned a minor planet number, was designated S/2011 (134340) 1 rather than S/2011 P 1, though the New Horizon team, who disagreed with the dwarf planet classification, used the latter. After a few months or years, when a newly discovered satellite's existence has been confirmed and its orbit computed, a permanent name is