With the discovery by the Hubble Space Telescope of a fifth tiny moon orbiting Pluto, interest continues to mount about this peculiar system.
Now, there is a suggestion on Discovery.com that the system is actually a Double Planet with four moons (see the image).
The four tiny moons, all discovered by Hubble in the past seven years, do not orbit Pluto itself. Instead, they orbit the center of mass of the Pluto-Charon system.
Charon is 12% the mass of Pluto, and could well qualify as a Kuiper Belt Object (KBO) and is perhaps a dwarf planet itself.
Ceres is a dwarf planet in the Asteroid belt, with a mass of 0.000 15 that of Earth. Pluto’s mass is 0.002 2 of Earth, which would make Charon’s mass 0.000 27 that of Earth (more than Ceres).