TITLE: GCN CIRCULAR NUMBER: 41903 SUBJECT: GRB 250920C: Fermi GBM Final Real-time Localization DATE: 25/09/20 15:36:01 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 15:25:17 UT on 20 Sep 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250920C (trigger 780074722.062672 / 250920643). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 47.6, Dec = -26.7 (J2000 degrees, equivalent to J2000 03h 10m, -26d 41'), with a statistical uncertainty of 1.2 degrees. The angle from the Fermi LAT boresight is 93.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250920643/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/bn250920643/q... The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250920643/q... View this GCN Circular online at https://gcn.nasa.gov/circulars/41903. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...