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proto-planet comparison table

Subject	has definition	is a kind of
planet	An object that formed in the disk surrounding a star. Unlike stars, planets do not produce light of their own but merely reflect that of the star(s) they orbit. Planets can have natural satellites.	celestial body
proto-planet	Early stage in the formation of planets according to the theory by which planetary systems evolve through the condensation of gas clouds surrounding a young star. The theory is not, however, generally accepted.	planet

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