The positions of over 1000 gamma-ray bursts detected with the BATSE
experiment on board of the Compton Gamma Ray Observatory are uniformly
and randomly distributed in the sky, with no significant concentration
to the galactic plane or to the galactic center. This is consistent with
the previous, less precise experiments. The strong gamma-ray bursts
have the intensity distribution consistent with the number density
independent of
distance in the Euclidean space. The weak gamma-ray bursts are
relatively rare, indicating that either their number density is reduced
at large distances or that the space in which they are distributed is
non-Euclidean. In other words, we appear to be at the center of a
spherical and bounded distribution of bursters. This is consistent with the
distribution of all objects that are known to be at cosmological distances
(like galaxies and quasars), but inconsistent with the distribution of any
objects which are known to be in our galaxy (like stars and globular
clusters). If the bursters are indeed at cosmological
distances then a simple prediction follows: the weakest bursts should
be redshifted, i.e. on average their durations should be longer
and their spectra should be softer than the corresponding quantities for
the strong bursts. There is evidence for both effects in the BATSE
data.
At this time the cosmological distance scale is favored above the
galactic one, but is not proven. A definite proof (or dis-proof)
of the galactic distance scale could be provided with the results
of a search for very weak bursts in the Andromeda galaxy (M31) with
an instrument times more sensitive than BATSE.
If the bursters are indeed at cosmological distances then they are the
most luminous
sources of electromagnetic radiation known in the universe. At this time we
have no clue as to their nature, even though well over a hundred suggestions
were published in the scientific journals.
An experiment providing arc second positions would greatly
improve the likelihood that counterparts of gamma-ray bursters are finally
detected. A new interplanetary network would offer the best opportunity.