Implications of the interstellar object 1I/'Oumuamua for planetary dynamics and planetesimal formation

  title={Implications of the interstellar object 1I/'Oumuamua for planetary dynamics and planetesimal formation},
  author={Sean N. Raymond and Philip J. Armitage and Dimitri Veras and Elisa V. Quintana and Thomas Barclay},
  journal={Monthly Notices of the Royal Astronomical Society},
'Oumuamua, the first bona-fide interstellar planetesimal, was discovered passing through our Solar System on a hyperbolic orbit. This object was likely dynamically ejected from an extrasolar planetary system after a series of close encounters with gas giant planets. To account for 'Oumuamua's detection, simple arguments suggest that ~1 Earth-mass of planetesimals are ejected per Solar mass of Galactic stars. However, that value assumes mono-sized planetesimals. If the planetesimal mass… 

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