Is there an exoplanet in the Solar System

  title={Is there an exoplanet in the Solar System},
  author={Alexander J. Mustill and Sean N. Raymond and Melvyn B. Davies},
  journal={Monthly Notices of the Royal Astronomical Society},
We investigate the prospects for the capture of the proposed Planet 9 from other stars in the Sun's birth cluster. Any capture scenario must satisfy three conditions: the encounter must be more distant than ∼150 au to avoid perturbing the Kuiper belt; the other star must have a wide-orbit planet (a ≳ 100 au); the planet must be captured on to an appropriate orbit to sculpt the orbital distribution of wide-orbit Solar system bodies. Here we use N-body simulations to show that these criteria may… 

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