TITLE: GCN CIRCULAR NUMBER: 29795 SUBJECT: GRB 210411D: Fermi GBM Final Real-time Localization DATE: 21/04/11 16:41:35 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM The Fermi GBM team reports the detection of a likely LONG GRB At 16:31:10 UT on 11 Apr 2021, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 210411D (trigger 639851475.876502 / 210411688). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 358.5, Dec = 24.3 (J2000 degrees, equivalent to J2000 23h 53m, 24d 18'), with a statistical uncertainty of 3.6 degrees. The angle from the Fermi LAT boresight is 55.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn210411688/quicklook/glg_skymap_all_bn210411688.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/bn210411688/quicklook/glg_healpix_all_bn210411688.fit The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn210411688/quicklook/glg_lc_medres34_bn210411688.gif