TITLE:   GCN CIRCULAR
NUMBER:  41819
SUBJECT: GRB 250912A: Fermi GBM Final Real-time Localization
DATE:    25/09/12 21:17:50 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 21:06:23 UT on 12 Sep 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250912A (trigger 779403988.636734 / 250912879).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 13.9, Dec = 24.3 (J2000 degrees, equivalent to J2000 00h 55m, 24d 18'), with a statistical uncertainty of 7.9 degrees.

The angle from the Fermi LAT boresight is 62.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250912879/quicklook/glg_skymap_all_bn250912879.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/bn250912879/quicklook/glg_healpix_all_bn250912879.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250912879/quicklook/glg_lc_medres34_bn250912879.gif