TITLE:   GCN CIRCULAR
NUMBER:  30030
SUBJECT: GRB 210516A: Fermi GBM Final Real-time Localization
DATE:    21/05/16 23:44:53 GMT
FROM:    Fermi GBM Team at MSFC/Fermi-GBM  <do_not_reply@GIOC.nsstc.nasa.gov>

The Fermi GBM team reports the detection of a likely LONG GRB

At 23:34:46 UT on 16 May 2021, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 210516A (trigger 642900891.497152 / 210516982).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 22.1, Dec = 74.9 (J2000 degrees, equivalent to J2000 01h 28m, 74d 54'), with a statistical uncertainty of 9.5 degrees.

The angle from the Fermi LAT boresight is 116.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn210516982/quicklook/glg_skymap_all_bn210516982.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/bn210516982/quicklook/glg_healpix_all_bn210516982.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2021/bn210516982/quicklook/glg_lc_medres34_bn210516982.gif