TITLE: GCN CIRCULAR NUMBER: 43800 SUBJECT: GRB 260221B: Fermi GBM Final Real-time Localization DATE: 26/02/21 23:29:14 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 SHORT GRB At 23:18:22 UT on 21 Feb 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260221B (trigger 793408707.776836 / 260221971). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 328.4, Dec = 75.0 (J2000 degrees, equivalent to J2000 21h 53m, 75d 00'), with a statistical uncertainty of 8.4 degrees. The angle from the Fermi LAT boresight is 12.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260221971/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/bn260221971/q... The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260221971/q... View this GCN Circular online at https://gcn.nasa.gov/circulars/43800. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...