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Oort cloud

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noun \ˈȯrt-\

Definition of Oort cloud

  1. :  a spherical shell of cometary bodies believed to surround the sun far beyond the orbits of the outermost planets and from which some are dislodged when perturbed to fall toward the sun — compare kuiper belt



Origin of oort cloud

Jan Oort †1992 Dutch astronomer


First Known Use: 1974


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