Pluto

It takes Pluto 90,465 days to do 1 orbit around the sun. It takes Pluto 6 days and 9 hours to make one full rotation. Pluto was thought to be the god to whom all men must eventually go. Romans believed him to be the god of the underworld. His name in Greece was Hades. Because Pluto is so small you would be very light if you visited. If you weigh 70 pounds on Earth, you would only weigh 4 pounds on Pluto. Pluto is smaller than 7 of the moons in the Solar System.  Because it is so small many scientists don't consider it a planet at all.  In 1999 a group of scientists attempted to redesignate Pluto as a comet.On August 24th, 2006 Pluto's status was officially changed from planet to dwarf planet. For decades children have been taught that there are nine planets in the Solar System. However, with this change, there are now only eight planets.
Pluto has never been visited by space craft.  Because we have never sent probes to this planet we know very little about it. Pluto has three moons. The largest is named Charon.  Charon is only slightly smaller than its parent Pluto.  For this reason Pluto and Charon are often called a double system.  The Earth and its moon Luna are sometimes considered double planets.