TITLE: GCN CIRCULAR NUMBER: 27177 SUBJECT: GRB 200224A: Tautenburg observations DATE: 20/02/24 07:37:12 GMT FROM: Sylvio Klose at TLS Tautenburg B. Stecklum, S. Klose, A. Nicuesa Guelbenzu, and S. Melnikov (all Tautenburg) report: We observed the field of GRB 200224A (T0=03:24:49 UT; Ukwatta et al., GCN 27173) with the Tautenburg 1.34m Schmidt telescope equipped with the TAUKAM 6k x 6k CCD camera and the wide V-band filter (VB). The transmission curve of this filter closely follows the Gaia GBP filter. Observations started at 04:09:53 UT and consisted of 5x3 min exposures. Based on several Gaia DR2 stars in the field within 1 arcmin radius about the afterglow position, we measure for the optical transient (Sota et al., GCN 27176) at RA, DEC (J2000) = 16:35:04.11, +41:36:42.4 (+/- 0.5 arcsec) the following preliminary Vega magnitude: mean time t = Feb 24, 04:18:01 UT; t-T0 = 53m 12s; VB = 21.83 +/- 0.10. [GCN OPS NOTE(24feb20): This is the sixth Circular in the sequence of 8 circulars which were all labeled A because of the sequence assigner being offline. This circular was correctly labelled A.]