TITLE:   GCN CIRCULAR
NUMBER:  44317
SUBJECT: GRB 260417A: Fermi GBM Final Real-time Localization
DATE:    26/04/17 00:21:39 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 00:10:05 UT on 17 Apr 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260417A (trigger 798077410.198084 / 260417007).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 252.0, Dec = -19.8 (J2000 degrees, equivalent to J2000 16h 48m, -19d 48'), with a statistical uncertainty of 3.4 degrees.

The angle from the Fermi LAT boresight is 81.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260417007/quicklook/glg_skymap_all_bn260417007.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/bn260417007/quicklook/glg_healpix_all_bn260417007.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260417007/quicklook/glg_lc_medres34_bn260417007.gif