TITLE: GCN CIRCULAR NUMBER: 44249 SUBJECT: GRB 260409A: Fermi GBM Final Real-time Localization DATE: 26/04/09 17:43:22 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 17:32:45 UT on 9 Apr 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260409A (trigger 797448770.671026 / 260409731). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 298.8, Dec = 61.6 (J2000 degrees, equivalent to J2000 19h 55m, 61d 36'), with a statistical uncertainty of 2.0 degrees. The angle from the Fermi LAT boresight is 121.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260409731/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/bn260409731/q... The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260409731/q... View this GCN Circular online at https://gcn.nasa.gov/circulars/44249. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...