TITLE: GCN CIRCULAR NUMBER: 43324 SUBJECT: GRB 260104C: Fermi GBM Final Real-time Localization DATE: 26/01/05 00:08:31 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov> The Fermi GBM team reports the detection of a likely LONG GRB At 23:57:57 UT on 4 Jan 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260104C (trigger 789263882.41794 / 260104999). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 312.7, Dec = -26.1 (J2000 degrees, equivalent to J2000 20h 50m, -26d 06'), with a statistical uncertainty of 9.3 degrees. The angle from the Fermi LAT boresight is 101.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260104999/q... The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260104999/q... The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260104999/q... View this GCN Circular online at https://gcn.nasa.gov/circulars/43324. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...