Gravitational scattering as a possible origin for giant planets at small stellar distances

  title={Gravitational scattering as a possible origin for giant planets at small stellar distances},
  author={S. J. Weidenschilling and Francesco Marzari},
THE recent discoveries1–4 of massive planetary companions orbiting several solar-type stars pose a conundrum. Conventional models5,6 for the formation of giant planets (such as Jupiter and Saturn) place such objects at distances of several astronomical units from the parent star, whereas all but one of the new objects are on orbits well inside 1 AU; these planets must therefore have originated at larger distances and subsequently migrated inwards. One suggested migration mechanism invokes tidal… Expand
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  • Science
  • 1995
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  • G. Wetherill
  • Physics, Medicine
  • Astrophysics and space science
  • 1994
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