Variability of GRB 050709

Two images taken with the 1.5-m telescope at La Silla of the short gamma-ray burst afterglow. The panel (a) is the image taken on July 11, while panel (b) shows the same field one week later, on July 18. Only the galaxy is now visible: the afterglow has faded away in the time span of one week. Panel (c) shows the difference between panels (a) and (b) clearly revealing the short gamma-ray burst visible light.