Nemesis reconsidered: Nemesis reconsidered

  title={Nemesis reconsidered: Nemesis reconsidered},
  author={Adrian L. Melott and Richard K. Bambach},
  journal={Monthly Notices of the Royal Astronomical Society: Letters},
  • A. Melott, R. Bambach
  • Published 2 July 2010
  • Physics
  • Monthly Notices of the Royal Astronomical Society: Letters
The hypothesis of a companion object (Nemesis) orbiting the Sun was motivated by the claim of a terrestrial extinction periodicity, thought to be mediated by comet showers. The orbit of a distant companion to the Sun is expected to be perturbed by the Galactic tidal field and encounters with passing stars, which will induce variation in the period. We examine the evidence for the previously proposed periodicity, using two modern, greatly improved paleontological datasets of fossil biodiversity… 

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