2026-05-10T16:30:03.987Z | rev 0
Xing-Hao Luo, Chen-Wei Wang, Shao-Lin Xiong (IHEP) report on behalf of GECAM team:
GECAM-B was triggered on-ground by GRB 260510A, at 2026-05-10T02:46:35.000 UTC (denoted as T0), which is also detected by Fermi/GBM (Fermi GBM team, GCN #44508).
According to the GECAM-B light curves in about 70-6000 keV, this burst mainly consists of multiple pulses with a duration (T90) of 38 +6/-5 s.
The GECAM-B light curve can be found here:
https://www.bursthub.cn//admin/static/gecambgrb260510A.png
Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) mission originally consists of two micro-satellites (GECAM-A and GECAM-B) launched in Dec. 2020. As the third member of GECAM constellation, GECAM-C was launched onboard SATech-01 experimental satellite in July 2022. GECAM mission is funded by the Chinese Academy of Sciences (CAS).
GCN 44511: Fermi GRB 260510A: Global MASTER-Net observations report
2026-05-10T06:30:25.585Z | rev 0
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, I. Gorbunov (Lomonosov MSU),
O.Gress, N.Budnev (ISU),
C.Francile, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A.Sosnovskij (CrAO),
A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity),
D.Buckley (SAAO),
R.Rebolo (The Instituto de Astrofisica de Canarias),
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory)
MASTER-OAFA robotic telescope [1] located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 260510A ( Fermi GBM team, GCN 44508) errorbox 12795 sec after notice time and 12848 sec after trigger time at 2026-05-10 06:20:28 UT, with upper limit up to 17.6 mag. The observations began at zenith distance = 80 deg. The sun altitude is -61.8 deg.
The galactic latitude b = -73 deg., longitude l = 333 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=3304437
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
12879 | 2026-05-10 06:20:28 | MASTER-OAFA | (00h 01m 07.12s , -42d 06m 59.6s) | C | 60 | 17.0 |
12956 | 2026-05-10 06:21:45 | MASTER-OAFA | (00h 01m 04.44s , -42d 05m 38.2s) | C | 60 | 16.9 |
13034 | 2026-05-10 06:23:03 | MASTER-OAFA | (00h 01m 02.62s , -44d 07m 12.4s) | C | 60 | 17.4 |
13109 | 2026-05-10 06:24:18 | MASTER-OAFA | (00h 01m 04.74s , -44d 05m 38.9s) | C | 60 | 17.5 |
13186 | 2026-05-10 06:25:35 | MASTER-OAFA | (00h 00m 59.38s , -44d 06m 16.7s) | C | 60 | 17.6 |
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
GCN 44508: GRB 260510A: Fermi GBM Final Real-time Localization
2026-05-10T02:57:06.726Z | rev 0
The Fermi GBM team reports the detection of a likely LONG GRB
At 02:46:19 UT on 10 May 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260510A (trigger 800073984.34868 / 260510115).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 0.5, Dec = -41.9 (J2000 degrees, equivalent to J2000 00h 02m, -41d 53'), with a statistical uncertainty of 6.1 degrees.
The angle from the Fermi LAT boresight is 84.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260510115/quicklook/glg_skymap_all_bn260510115.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/bn260510115/quicklook/glg_healpix_all_bn260510115.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260510115/quicklook/glg_lc_medres34_bn260510115.gif