TITLE:   GCN CIRCULAR
NUMBER:  42192
SUBJECT: GRB 251010A: Fermi GBM Final Real-time Localization
DATE:    25/10/10 17:55:05 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 17:44:25 UT on 10 Oct 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 251010A (trigger 781811070.725816 / 251010739).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 214.0, Dec = 56.6 (J2000 degrees, equivalent to J2000 14h 16m, 56d 36'), with a statistical uncertainty of 4.5 degrees.

The angle from the Fermi LAT boresight is 103.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251010739/quicklook/glg_skymap_all_bn251010739.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251010739/quicklook/glg_healpix_all_bn251010739.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251010739/quicklook/glg_lc_medres34_bn251010739.gif