{
  "bibcode": "2021GCN.29269....1R",
  "body": "I observed the field of GRB 210104A (Troja et al., GCN Circ. 29233)\nwith remote telescope T11 (0.50-m f/6.8 reflector + CCD + f/4.5 focal\nreducer) of iTelescope.Net in New Mexico Observatory. Three images\nwith AstroDon Luminance filter and with 300 seconds exposure time were\nobtained on 2021-01-05. Start time of exposures: 06:46:48 UT (~19.3 h.\nafter trigger; Binx1), 06:52:21 UT (Binx2) and 06:57:44 UT (Binx1). I\ndid not detect any optical transients (magnitude limit of about 21.0\nin stacked image).",
  "circularId": 29269,
  "createdOn": 1609928358000,
  "email": "filipp.romanov.27.04.1997@gmail.com",
  "subject": "GRB 210104A: iTelescope optical upper limit",
  "submitter": "Filipp Dmitrievich Romanov at Amateur astronomer  <filipp.romanov.27.04.1997@gmail.com>",
  "eventId": "GRB 210104A"
}