Not by popular demand the International Astronomical Union (IAU) reclassified Pluto from a planet to a "Dwarf Planet." There are four conditions that define a dwarf planet. (1) it has to orbit the Sun, (2) it has to have sufficient mass so that its internal gravitational forces shape it into a round object, (3) it has not cleared out its neighborhood around its orbiting path, and (4) is not a satellite of another planet.

Pluto was named after the Roman god of the dead who presides over eternal darkness. This distant object was discovered at the Lowell Observatory in 1930 by Clyde Tombaugh. Pluto orbit is inclines 17.2 degrees to the plane of the ecliptic and resides at distance of 39.5 (A. U.). Pluto is unlike the terrestrial and jovian planets and has always been the odd planet up until its reclassification due to its dissimilarities.

Pluto has a mass only 0.2% that of the Earth and is tilted a whopping 118° on its axis. Pluto has retrograde rotation on its axis and takes 6.4 days for a complete rotation. Pluto takes 248 years to orbit the Sun and is so far away from Earth that it is fainter than many stars. Pluto has three moons two of which were recently discovered. Charon, Pluto's largest moon was discovered in 1978 and now Nix and Hydra were discovered in 2006.

NASA has a probe known as New Horizons speeding toward Pluto and should arrive in 2015. If successful it will transmit back to Earth the first clear images ever of this far away object. For more information on New Horizons go to http://www.nasa.gov/mission_pages/newhorizons/main/index.html