{
  "bibcode": "2025GCN.40995....1R",
  "submitter": "Filipp Dmitrievich Romanov at Amateur astronomer <filipp.romanov.27.04.1997@gmail.com>",
  "eventId": "GRB 250706B",
  "createdOn": 1751835549177,
  "subject": "GRB 250706B: iTelescope optical observations",
  "body": "On 2025-07-06 I observed the field of GRB 250706B (Palmerio et al.,\nGCN Circ. 40989) remotely using the telescopes T33 (0.3-m f/9\nreflector + CCD with Astrodon Series II Red filter) and T17 (0.43-m\nf/6.8 reflector + CMOS with Astrodon Red-E filter) of iTelescope.Net\nat Siding Spring Observatory, Australia.\n\nThe exposure times of the photographs were 300 seconds, observations\nstarted at 19:56:23 UT (2h 50m after the trigger). I detected the\noptical afterglow in all images with the position (J2000.0):\n02:44:55.46 -50:03:40.1.\n\nI measured the magnitudes (compared to r' magnitudes of nearby stars\nfrom the APASS DR9 catalog: Henden et al., 2016):\n\nMid-time (UT) | Magnitude | Error | Telescope |\n19:58:53.3  16.852  0.073  T33\n20:04:55.9  16.790  0.046  T33\n20:10:58.5  16.756  0.110  T33\n20:17:00.3  16.752  0.071  T33\n\n20:05:50.8  16.738  0.040  T17\n20:11:47.9  16.875  0.054  T17\n20:17:43.6  16.833  0.076  T17\n\n\nMagnitudes were not corrected for Galactic extinction.\n\nF. D. Romanov (AAVSO).\n",
  "circularId": 40995,
  "submittedHow": "email"
}