A Galactic Origin for the Fast Radio Burst FRB010621
  The recent detection of Fast Radio Bursts (FRBs) has generated strong
interest in identifying the origin of these bright, non-repeating, highly
dispersed pulses. The principal limitation in understanding the origin of these
bursts is the lack of reliable distance estimates; their high dispersion
measures imply that they may be at cosmological distances ($0.1 < z < 1.0$).
Here we discuss new distance constraints to the FRB010621 (a.k.a J1852$-$08)
first reported by Keane. We use velocity resolved $H\alpha$ and $H\beta$
observations of diffuse ionised gas toward the burst to calculate an
extinction-corrected emission measure along the line of sight. We combine this
emission measure with models of Galactic rotation and of electron distribution
to derive a 90% probability of the pulse residing in the Galaxy. However, we
cannot differentiate between the two Galactic interpretations of Keane: a
neutron star with unusual pulse amplitude distribution or Galactic black hole
annihilation.
