TITLE:   GCN CIRCULAR
NUMBER:  43560
SUBJECT: GRB 260129A: Fermi GBM Final Localization
DATE:    26/01/29 18:53:30 GMT
FROM:    Christian Malacaria at INAF-OAR <cmalacaria.astro@gmail.com>

"The Fermi GBM team reports the detection of a likely Long GRB.

At 04:33:12 UT on 29 Jan 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located 
GRB 260129A (trigger 791353997 / 260129190). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 160.4, Dec = -46.8 (J2000 degrees, equivalent to J2000 10h 41m, -46d 48'), with a statistical uncertainty of 9.7 degrees. The angle from the Fermi LAT boresight is 20.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260129190/quicklook/glg_skymap_all_bn260129190.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/bn260129190/quicklook/glg_healpix_all_bn260129190.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260129190/quicklook/glg_lc_medres34_bn260129190.gif"