Is Pluto a Planet?

The debate about whether Pluto is a planet - generated by recent detections of hundreds of planetary objects in the outer solar system - continues. Many planetary scientists consider Pluto a planet because it orbits the Sun and it is large enough that its own gravity has pulled it into a spherical shape. Others disagree. Science is often contentious this way as new information is digested. This kind of debate is healthy in science.

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Scientists, educators and members of the public gathered for the Great Planet Debate in August 2008.
See how it turned out!

The Pluto Debate

Recent discoveries of hundreds of small planets in the outer solar system have started a planetary debate. These objects are thought to be part of a large collection of Pluto-sized and smaller bodies that forms a disk-shaped cloud of both small and large bodies beyond Pluto's orbit called the Kuiper Belt.

To learn more about the solar system classification and the discussions of Pluto as a planet, visit Yes, Pluto really is a Planet.