Nomads of the Galaxy

  title={Nomads of the Galaxy},
  author={L. Strigari and M. Barnab{\`e} and P. Marshall and R. Blandford},
  journal={Monthly Notices of the Royal Astronomical Society},
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… Expand

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Unbound or distant planetary mass population detected by gravitational microlensing
  • T. K. D. P. I. A. F. C. S. A. K. J. B. Y. P. M. A. W. Sumi Kamiya Bennett Bond Abe Botzler Fukui Furusaw, T. Sumi, +38 authors K. Ulaczyk
  • Physics, Medicine
  • Nature
  • 2011
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