{
  "bibcode": "2025GCN.41482....1F",
  "circularId": 41482,
  "subject": "GRB 250821C: Fermi GBM Final Real-time Localization",
  "submitter": "Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>",
  "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 23:42:00 UT on 21 Aug 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250821C (trigger 777512525.658232 / 250821988).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 104.3, Dec = -1.1 (J2000 degrees, equivalent to J2000 06h 57m, -1d 06'), with a statistical uncertainty of 15.0 degrees.\n\nThe angle from the Fermi LAT boresight is 90.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250821988/quicklook/glg_skymap_all_bn250821988.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250821988/quicklook/glg_healpix_all_bn250821988.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250821988/quicklook/glg_lc_medres34_bn250821988.gif\n",
  "eventId": "GRB 250821C",
  "submittedHow": "email",
  "createdOn": 1755820356577
}