GRB 250824A
GCN Circular 41572
Subject
GRID detection of GRB 250824A
Date
2025-08-28T02:17:34Z (a year ago)
From
GRID Student Team at Tsinghua University <grid@tsinghua.edu.cn>
Via
Web form
Longhao Li, Chenyu Wang and Zirui Yang report on behalf of the GRID Collaboration:
GRID-11B reports the detection of the GRB 250824A, which was also detected by Fermi/GBM (GCN Circular 41522).
The event was triggered with GRID on 2025-08-24 at 11:24:15 UTC. The measured burst duration (T90) is approximately 78.2 ± 5.6 seconds.
The GRID light curve of this event can be found at https://mirrors.tuna.tsinghua.edu.cn/GRID/data/GRID-GCN/GRB250824A/GRID_GRB250824A_ltcv.pdf.
GRID is a student-led project to monitor the transient gamma-ray sky with multiple detectors onboard different nanosatellites in the era of multi-messenger astronomy. For more information about GRID, please refer to the following references: https://doi.org/10.1007/s10686-019-09636-w and https://doi.org/10.1007/s10686-021-09819-4.
GCN Circular 41522
Subject
GRB 250824A: Fermi GBM Final Real-time Localization
Date
2025-08-24T11:34:48Z (a year 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 11:24:18 UT on 24 Aug 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250824A (trigger 777727463.376698 / 250824475).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 312.0, Dec = 49.5 (J2000 degrees, equivalent to J2000 20h 48m, 49d 30'), with a statistical uncertainty of 2.0 degrees.
The angle from the Fermi LAT boresight is 61.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250824475/quicklook/glg_skymap_all_bn250824475.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/bn250824475/quicklook/glg_healpix_all_bn250824475.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250824475/quicklook/glg_lc_medres34_bn250824475.gif