GRB 251012A
GCN Circular 42268
Subject
GRB 251012A: Glowbug gamma-ray detection of a likely short burst
Date
2025-10-14T20:31:56Z (a day ago)
From
C.C. Cheung at Naval Research Lab <Teddy.Cheung@nrl.navy.mil>
Via
Web form
C.C. Cheung, R. Woolf, M. Kerr, J.E. Grove (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge, D. Kocevski (MSFC), and M.S. Briggs (UAH) report:
The Glowbug gamma-ray telescope [1,2,3], operating on the International Space Station, reports the detection of GRB 251012A, which was also detected by Fermi/GBM (GCN 42207).
Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2025-10-12 14:46:26.104 with a duration of 0.16 s and a total significance of about 13.0 sigma. The light curve comprises a single peak.
The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.
Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC. It was launched on 2023 March 15 aboard the Department of Defense Space Test Program’s STP-H9 to the ISS, and operated until 2024 April when it was put in safe storage on orbit. Glowbug was removed from storage and resumed operation on 2025 September 12.
[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Woolf, R.S. et al. 2024, Proc. SPIE, 13151, id. 1315108
Distribution Statement A: Approved for public release. Distribution is unlimited.
GCN Circular 42207
Subject
GRB 251012A: Fermi GBM Final Real-time Localization
Date
2025-10-12T14:56:50Z (3 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 SHORT GRB
At 14:46:27 UT on 12 Oct 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 251012A (trigger 781973192.204998 / 251012616).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 291.6, Dec = 7.5 (J2000 degrees, equivalent to J2000 19h 26m, 7d 30'), with a statistical uncertainty of 9.9 degrees.
The angle from the Fermi LAT boresight is 59.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251012616/quicklook/glg_skymap_all_bn251012616.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251012616/quicklook/glg_healpix_all_bn251012616.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251012616/quicklook/glg_lc_medres34_bn251012616.gif