TITLE:   GCN CIRCULAR
NUMBER:  43836
SUBJECT: GRB 260225C: Fermi GBM Final Real-time Localization
DATE:    26/02/25 19:08:07 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 18:55:39 UT on 25 Feb 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260225C (trigger 793738544.90425 / 260225789).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 102.6, Dec = 69.3 (J2000 degrees, equivalent to J2000 06h 50m, 69d 17'), with a statistical uncertainty of 15.2 degrees.

The angle from the Fermi LAT boresight is 54.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260225789/quicklook/glg_skymap_all_bn260225789.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/bn260225789/quicklook/glg_healpix_all_bn260225789.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260225789/quicklook/glg_lc_medres34_bn260225789.gif