Although GRB 000131,
like other gamma - ray bursts, appears to have taken place
in a remote «early galaxy» (or «sub-galactic
clumps» of stars) that is smaller than today's luminous galaxies, astronomers found it difficult to detect that extremely dim, sub-galactic
clump of stars even with the Hubble
Space Telescope, as the observed fading of the afterglow indicated that the maximum brightness of the gamma - ray emission was explosion was at least 10,000 times brighter than its host galaxy.