Night of 20150331 Takahashi Mewlon AVT G031 with exposures of less than 1000 microseconds Invert Y to have N up and W to right Selected exposures from 23:20 to 23:54 Two images show the progression of the shadow of Callisto on the disk over this time period. A third is logarithmically stretched to show Io (left) and Callisto (fainter, on the right). The pdf is from XEphem at 23:45 local time.