Pluto's Dwarf Planet Family Could Get Bigger

From Discovery News - Top Stories:

Although Pluto was kicked out of the planetary club by the International Astronomical Union (IAU) four years ago, the passionate "Pluto debate" rumbles on. But the fact remains that even before discovery of Eris in 2005 by a Palomar Observatory team headed by Caltech's Mike Brown, Pluto's ranking as a planet in the solar system was tenuous at best. Eris was measured to be nearly 30 percent larger than Pluto; did that make Eris a planet too? No, but its discovery began a series of events that changed our understanding of the solar system forever.

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