{
  "bibcode": "2019GCN.26565....1R",
  "body": "I observed the optical afterglow of GRB 191221B (Laha et al., GCN Circ.\n26534) with remote telescope T32 (0.43-m f/6.8 reflector + FLI Proline\n16803 CCD) of iTelescope.Net in Siding Spring Observatory (Australia) on\n2019-12-22 since 13:28:52 UT (~16.8 hours after the trigger). Two images\nwere obtained in each band with Astrodon luminance filter and\nJohnson/Cousins V filter for 180 and 120 seconds (Binx2). I detected the\noptical afterglow in three images in the enhanced Swift-XRT position\n(Beardmore et al., GCN Circ. 26540); it not present in images from DSS\nPlate Finder.\n\nThe following magnitudes (mag. error ~ 0.2) were measured from comparison\nto nearby stars from APASS DR9 catalogue (Henden et al., 2016):\n\nTime of start  Exp.time  Mag.   Comp.star band  Filter\n----------------------------------------------------------\n13:28:52 UT    180 s     18.1        r'         Luminance\n13:32:58 UT    180 s     18.3        V          V\n13:36:51 UT    120 s     18.3        r'         Luminance\n13:39:46 UT    120 s     <17.9       V          V\n----------------------------------------------------------\n\nMagnitudes were not corrected for Galactic extinction.",
  "circularId": 26565,
  "createdOn": 1577060484000,
  "email": "filipp.romanov.27.04.1997@gmail.com",
  "subject": "GRB 191221B: iTelescope optical observations",
  "submitter": "Filipp Dmitrievich Romanov at Amateur astronomer  <filipp.romanov.27.04.1997@gmail.com>",
  "eventId": "GRB 191221B"
}