Pluto is reduced to a Dwarf Planet:
what gives?

Back in 2006, a lot of really smart astronomers and scientists got together at the International Astronomical Union Meeting and decided on what things were necessary for a celestial object to be called a planet. First, it must orbit the sun, it must have enough mass (be big enough) that it's own gravity will make it nearly round in shape, and it must be dominant enough to clear away smaller objects in its neighborhood. Unfortunately, Pluto falls a bit short. It does orbit the Sun, even though its orbit is irregular and not like those of the other larger planets in our solar system. It is round for sure and looks like a planet, but because it does not have enough mass, it can't or hasn't yet cleared away other smaller objects close by. So they decided that there would be a new classification called "Dwarf Planets", of which Pluto was the first to be included. There are several more of these types of planets that have been discovered, some even bigger than Pluto! Click on the buttons above to learn more about this fascinating planet far off at the edge of our solar system!