TITLE: GCN CIRCULAR NUMBER: 42385 SUBJECT: GRB 251023A: Fermi GBM Final Localization Correction DATE: 25/10/23 07:33:17 GMT FROM: A. Holzmann Airasca at University of Trento and INFN Bari <a.holzmannairasca@unitn.it> The Fermi GBM team reports the detection of a likely LONG GRB "At 05:57:43.66 UT on 23 October 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 251023A (trigger 782891868/251023248). This trigger was initially classified as distant particles by the flight software, but is in fact a GRB. The on-ground calculated location, using the Fermi GBM trigger data, is RA = 39.87, Dec = -6.53 (J2000 degrees, equivalent to J2000 02h 39m, -06d 31'), with a statistical uncertainty of 3.12 degrees. The angle from the Fermi LAT boresight is 89 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251023248/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/bn251023248/q... The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251023248/q..." View this GCN Circular online at https://gcn.nasa.gov/circulars/42385. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...