Spinning, Merged Moons

Explanation: Most inner moons in the solar system keep one face pointed toward their central planet; this animation shows that certainly isn't the case with the small moons of Pluto, which behave like spinning tops. Pluto is shown at center with, in order, from smaller to wider orbit: Charon, Styx, Nix, Kerberos and Hydra.


Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute