TITLE: GCN CIRCULAR NUMBER: 41660 SUBJECT: GRB 250902B: Fermi GBM Final Real-time Localization DATE: 25/09/02 18:56:35 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 18:45:34 UT on 2 Sep 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250902B (trigger 778531539.099344 / 250902782). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 82.3, Dec = -5.0 (J2000 degrees, equivalent to J2000 05h 29m, -5d 00'), with a statistical uncertainty of 1.4 degrees. The angle from the Fermi LAT boresight is 20.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250902782/q... The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250902782/q... The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250902782/q... View this GCN Circular online at https://gcn.nasa.gov/circulars/41660. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...