Nomads of the Galaxy

@article{Strigari2012NomadsOT,
  title={Nomads of the Galaxy},
  author={Louis E. Strigari and Matteo Barnab{\`e} and Philip J. Marshall and Roger D. Blandford},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2012},
  volume={423},
  pages={1856-1865}
}
We estimate that there may be up to ∼105 compact objects in the mass range 10−8–10−2 M⊙ per-main-sequence star that are unbound to a host star in the Galaxy. We refer to these objects as nomads; in the literature a subset of these are sometimes called free-floating or rogue planets. Our estimate for the number of Galactic nomads is consistent with a smooth extrapolation of the mass function of unbound objects above the Jupiter-mass scale, the stellar mass density limit and the metallicity of… 

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