Pluto's entire moon system is believed to have formed by a collision between the dwarf planet and another planet-sized body early in the history of the solar system. The smashup flung material that coalesced into the family of satellites observed around Pluto.
"The moons form a series of neatly nested orbits, a bit like Russian dolls," said team lead Mark Showalter of the SETI Institute in Mountain View, Calif.
The known moons of Pluto are:
- Charon: Discovered in 1978, this small moon is almost half the size of Pluto. It is so big Pluto and Charon are sometimes referred to as a double planet system.
- Nix and Hydra: These small moons were found in 2005 by a Hubble Space Telescope team studying the Pluto system.
- Kerberos: Discovered in 2011, this tiny moon is located between the orbits of Nix and Hydra.
- Styx: Discovered in 2012, this little moon was found by a team of scientists search for potential hazards to the New Horizons spacecraft flyby in 2015.
Scientists are searching for more possible moons orbiting Pluto and also signs of a possible debris field generated by the theoretical impact billions of years ago.