Planetesimals to brown dwarfs: What is a planet?

@article{Basri2006PlanetesimalsTB,
  title={Planetesimals to brown dwarfs: What is a planet?},
  author={Gibor S. Basri and Michael E. Brown},
  journal={Annual Review of Earth and Planetary Sciences},
  year={2006},
  volume={34},
  pages={193-216}
}
The past 15 years have brought about a revolution in our understanding of our Solar System and other planetary systems. During this time, discoveries include the first Kuiper belt objects (KBOs), the first brown dwarfs, and the first extrasolar planets. Although discoveries continue apace, they have called into question our previous perspectives on planets, both here and elsewhere. The result has been a debate about the meaning of the word “planet” itself. It is clear that scientists do not… 

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