TITLE: GCN CIRCULAR NUMBER: 40571 SUBJECT: GRB 250529B: Fermi GBM Final Real-time Localization DATE: 25/05/29 11:08:59 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 10:58:24 UT on 29 May 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250529B (trigger 770209109.316756 / 250529457). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 149.1, Dec = 71.6 (J2000 degrees, equivalent to J2000 09h 56m, 71d 35'), with a statistical uncertainty of 2.9 degrees. The angle from the Fermi LAT boresight is 121.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250529457/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/bn250529457/q... The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250529457/q... View this GCN Circular online at https://gcn.nasa.gov/circulars/40571. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...