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"And now, for something completely different."
In August 2006, the International Astronomical Union classified Pluto as a dwarf planet because its mass is only 0.07 times that of the mass of the other objects in its orbit (Earth's mass, by contrast, is 1.7 million times the remaining mass in its own orbit). Then, in June 2008 Pluto was re-classified as a sub-class of dwarf planet, known as a plutoid, which refers to Pluto and other objects that have an orbital semi-major axis greater than that of Neptune and enough mass to be of near-spherical shape.
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