GCN Circular 45842
SVOM GRB261007.27: Global MASTER-Net observations report
From: Vladimir Lipunov at Moscow State U/Krylov Obs
Issued: 2026-10-07 17:56 UTC
Why this event is posted: every one of the gamma-ray bursts is posted.
M. Segura, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA)
V.Lipunov, E.Gorbovskoy, A.Kuznetsov, K.Zhirkov, I.Panchenko, N.Tiurina, P.Balanutsa, V.Topolev, D.Vlasenko,
G.Antipov, A.Sankovich, Yu.Tselik, Ya..Kechin, V.Senik, A.Chasovnikov, K.Labsina (Lomonosov MSU)
D.Buckley (SAAO),
A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity)
A.Sosnovskij (Lomonosov MSU)
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory)
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory)
R.Rebolo (The Instituto de Astrofisica de Canarias)
O.Gress, N.Budnev(ISU)
MASTER-OAFA robotic telescope [1] located in Argentina (OAFA observatory of San Juan National University) was pointed to the SVOM GRB261007.27 (trigger No 1791354426,00h 46m 26.14s , -17d 41m 36.2s, R=0.0133) errorbox 1673 sec after trigger time at 2026-10-07 06:54:59 UT, with upper limit up to 19.7 mag. The observations began at zenith distance = 38 deg. The sun altitude is -38.3 deg.
The galactic latitude b = -80 deg., longitude l = 119 deg.
Real time updated cover map and OT discovered available here:
GRB261007.27 page :: MASTER Database :: MASTER Net (master.sai.msu.ru)
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
1723 | 2026-10-07 06:54:59 | MASTER-OAFA | (00h 45m 40.99s , -17d 45m 01.6s) | C | 100 | 19.7 |
1839 | 2026-10-07 06:56:45 | MASTER-OAFA | (00h 45m 41.02s , -17d 45m 00.3s) | C | 120 | 17.9 |
1975 | 2026-10-07 06:58:51 | MASTER-OAFA | (00h 45m 41.02s , -17d 44m 59.8s) | C | 140 | 18.0 |
2137 | 2026-10-07 07:01:17 | MASTER-OAFA | (00h 45m 41.07s , -17d 44m 59.5s) | C | 170 | 17.0 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
[1] - V.M. Lipunov, V.G. Kornilov, E.S. Gorbovskoy, N.A. Tiurina & A.S.Kuznetsov, 2023, Astronomical Robotic Networks and Operative Multichanel Astrophysics, Lomonosov MSU PRESS, 591pp.
http : // www.pereplet.ru/lipunov/625.html
Every one of the gamma-ray bursts GCN reports is posted here.
Relayed automatically from NASA's General Coordinates Network.
In plain words Routine
The SVOM satellite detected a burst of gamma rays, the most energetic form of light, on 7 October 2026. It came from a patch of sky in the southern constellation region near right ascension 00h 46m, declination -17.7 degrees, far from the plane of our Galaxy. About 28 minutes after the burst, a robotic telescope in Argentina (MASTER-OAFA) looked at that spot and saw no visible afterglow. It could only say that anything there was fainter than roughly magnitude 17 to 19.7, so no counterpart in visible light has been found yet. No distance or other details are given in this report.
How unusual is it? This is a typical gamma-ray burst report: the only follow-up is a visible-light non-detection, with no afterglow, distance measurement or other unusual feature. A redshift or an afterglow found by other telescopes would raise it to notable.
Written by an AI model (claude-sonnet-5-5) from the official reports in this thread; last updated . It may contain mistakes: the reports themselves are the authority.
GRB 261007.27