TITLE:   GCN CIRCULAR
NUMBER:  25431
SUBJECT: GRB 190821A: T60 Les Makes optical detection of the afterglow
DATE:    19/08/21 18:13:19 GMT
FROM:    Alain Klotz at IRAP-CNRS-OMP  <Alain.Klotz@free.fr>

Klotz A., Noysena.K., Atteia J.L. (CNRS-OMP-IRAP),
Boer, M., Eymar, L. (CNRS-ARTEMIS),
Gendre B. (UWA - Univ. Western Australia)
Peyrot, A., Teng J.P., Thierry P. (Les Makes observatory)
report:

We imaged the field of GRB 190821A detected by SWIFT
(trigger 921722) with the T60 tele-operated telescope (D=60cm)
located at Les Makes Observatory, Reunion Island, France.

The observations started 790s after the GRB trigger.
On the first image of 120s (Clear filter) we detect the
optical afterglow compatible with the position of XRT
(Lien et al. GCNC 25427).

start  end    R
(sec) (sec)
790   910   18.4 +/- 0.2

Further images are comming.

Magnitudes were estimated with the nearby NOMAD1 stars
and are not corrected for galactic dust extinction.