TITLE:   GCN CIRCULAR
NUMBER:  45550
SUBJECT: GRB 260910B: Fermi GBM Final Real-time Localization
DATE:    26/09/10 23:27:13 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 23:16:44 UT on 10 Sep 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260910B (trigger 810775009.56521 / 260910970).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 260.8, Dec = -0.7 (J2000 degrees, equivalent to J2000 17h 23m, 0d 42'), with a statistical uncertainty of 6.2 degrees.

The angle from the Fermi LAT boresight is 94.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260910970/quicklook/glg_skymap_all_bn260910970.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/bn260910970/quicklook/glg_healpix_all_bn260910970.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260910970/quicklook/glg_lc_medres34_bn260910970.gif