GCN Circular 45464
Subject
GRB 260829A: Fermi GBM Final Real-time Localization
Event
Date
2026-08-29T06:18:41Z (4 days ago)
From
Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>
Via
email
The Fermi GBM team reports the detection of a likely LONG GRB
At 06:08:09 UT on 29 Aug 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260829A (trigger 809676494.389126 / 260829256).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 242.3, Dec = -34.6 (J2000 degrees, equivalent to J2000 16h 09m, -34d 36'), with a statistical uncertainty of 1.0 degrees.
The angle from the Fermi LAT boresight is 47.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260829256/quicklook/glg_skymap_all_bn260829256.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/bn260829256/quicklook/glg_healpix_all_bn260829256.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260829256/quicklook/glg_lc_medres34_bn260829256.gif