TITLE: GCN CIRCULAR NUMBER: 20989 SUBJECT: GRB 170405A: TAROT Reunion observatory optical observations DATE: 17/04/06 02:22:43 GMT FROM: Alain Klotz at IRAP-CNRS-OMP Klotz A., Turpin D., Atteia J.L. (CNRS-OMP-IRAP), Boer, M., Laugier, R. (CNRS-ARTEMIS), Gendre B. (UVI - Etelman Obs.) Thierry P. (Auragne Observatory, France), Klotz A.N.O. (Guitalens Observatory, France) report: We imaged the field of GRB 170405A detected by SWIFT (trigger 745797) with the TAROT robotic telescope (D=18cm) located at the Reunion observatory, France. The observations started 3.84h after the GRB trigger. We detected the OT (Troja et al., GCN 20984; Hui & Meegan, GCN 20986; Vianello & Kocevski, GCN 20987; Malesani, GCNC 20988): t0+3.84h to t0+3.97h : R=19.0 +/- 0.2 Magnitudes were estimated with the nearby NOMAD1 stars and are not corrected for galactic dust extinction.