The evolution of comets in the Oort cloud and Kuiper belt

  title={The evolution of comets in the Oort cloud and Kuiper belt},
  author={S. Alan Stern},
  • S. Stern
  • Published 7 August 2003
  • Physics
  • Nature
Comets are remnants from the time when the outer planets formed, ∼4–4.5 billion years ago. They have been in storage since then in the Oort cloud and Kuiper belt—distant regions that are so cold and sparsely populated that it was long thought that comets approaching the Sun were pristine samples from the time of Solar System formation. It is now recognized, however, that a variety of subtle but important evolutionary mechanisms operate on comets during their long storage, so they can no longer… 

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