WASP-8b: A retrograde transiting planet in a multiple system

  title={WASP-8b: A retrograde transiting planet in a multiple system},
  author={Didier Queloz and David R. Anderson and Andrew Collier Cameron and Micha{\"e}l Gillon and Leslie Hebb and Coel Hellier and Pierre F. L. Maxted and Francesco A. Pepe and Don Pollacco and Damien S'egransan and Barry Smalley and Amaury H. M. J. Triaud and St{\'e}phane Udry and Richard G. West},
We report the discovery of WASP-8b, a transiting planet of 2.25 ± 0.08 MJup on a strongly inclined eccentric 8.15-day orbit, moving in a retrograde direction to the rotation of its late-G host star. Evidence is found that the star is in a multiple stellar system with two other companions. The dynamical complexity of the system indicates that it may have experienced secular interactions such as the Kozai mechanism or a formation that differs from the “classical” disc-migration theory. 

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