TITLE: GCN CIRCULAR NUMBER: 30865 SUBJECT: GRB 210923A: Fermi GBM Final Real-time Localization DATE: 21/09/23 11:57:13 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM The Fermi GBM team reports the detection of a likely SHORT GRB At 11:49:36 UT on 23 Sep 2021, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 210923A (trigger 654090581.820056 / 210923493). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 90.0, Dec = -6.5 (J2000 degrees, equivalent to J2000 06h 00m, -6d 30'), with a statistical uncertainty of 10.9 degrees. The angle from the Fermi LAT boresight is 47.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn210923493/quicklook/glg_skymap_all_bn210923493.png The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn210923493/quicklook/glg_healpix_all_bn210923493.fit The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn210923493/quicklook/glg_lc_medres34_bn210923493.gif