TITLE: GCN CIRCULAR NUMBER: 44901 SUBJECT: GRB 260610B: Fermi GBM Final Localization DATE: 26/06/11 01:29:13 GMT FROM: Matt Godwin The Fermi GBM team reports the detection of a likely LONG GRB "At 23:46:14.25 UT on 10 June 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260610B (trigger 802827979/260610990). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 218.66, Dec = 23.94 (J2000 degrees, equivalent to J2000 14h 34m, +23d 56'), with a statistical uncertainty of 2.77 degrees. The angle from the Fermi LAT boresight is 84 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260610990/quicklook/glg_skymap_all_bn260610990.png The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260610990/quicklook/glg_healpix_all_bn260610990.fit The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260610990/quicklook/glg_lc_medres34_bn260610990.gif"