Fifth Moon Discovered Orbiting Pluto . ... Credit Copyright: NASA , ESA , Mark Showalter ( SETI Institute ) Explanation: A fifth moon has been discovered orbiting Pluto. The moon was discovered earlier this month in images taken by the Hubble Space Telescope in preparation for the New Horizons mission's scheduled flyby of Pluto in 2015. Pictured above , the moon is currently seen as only a small blip that moves around the dwarf planet as the entire system slowly orbits the Sun. ...