Skip to main content
Introducing Einstein Probe, Astro Flavored Markdown, and Notices Schema v4.0.0. See news and announcements

GCN Circular 30671

GRB 210821A: Fermi GBM Final Real-time Localization
2021-08-21T07:51:40Z (3 years ago)
Fermi GBM Team at MSFC/Fermi-GBM <>
The Fermi GBM team reports the detection of a likely LONG GRB

At 07:40:28 UT on 21 Aug 2021, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 210821A (trigger 651224433.594692 / 210821320).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 49.3, Dec = -6.9 (J2000 degrees, equivalent to J2000 03h 17m, -6d 54'), with a statistical uncertainty of 2.0 degrees.

The angle from the Fermi LAT boresight is 87.0 degrees.

The skymap can be found here:

The HEALPix FITS file, including the estimated localization systematic, can be found here:

The GBM light curve can be found here:
Looking for U.S. government information and services? Visit