GRB 261024B
GCN Circular 46022
Subject
GRB 261024B: Fermi GBM Final Real-time Localization
Date
2026-10-24T22:38:08Z (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 22:27:33 UT on 24 Oct 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 261024B (trigger 814573658.65781 / 261024936).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 187.3, Dec = 32.4 (J2000 degrees, equivalent to J2000 12h 29m, 32d 23'), with a statistical uncertainty of 19.3 degrees.
The angle from the Fermi LAT boresight is 41.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn261024936/quicklook/glg_skymap_all_bn261024936.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/bn261024936/quicklook/glg_healpix_all_bn261024936.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn261024936/quicklook/glg_lc_medres34_bn261024936.gif