TITLE: GCN CIRCULAR NUMBER: 21752 SUBJECT: LIGO/Virgo G299232: PIRATE observations of MASTER OT J033744.97+723159.0 DATE: 17/08/29 16:27:50 GMT FROM: Dean Roberts at PIRATE D. Roberts, U. Kolb & M.Morrell (The Open University) reporting on behalf of the PIRATE group: We observed the field of MASTER OT J033744.97+723159.0 (Lipunov et al., GCN Circ. 21719) with our 0.43m robotic telescope at Teide Observatory, Tenerife, Spain. Observations were taken at two epochs between 2017-08-28T23:51 to 2017-08-29T00:27 and 2017-08-29T03:33 to 2017-08-29T04:09. In total 12 images were taken in the Baader B filter and 12 images in the Baader R filter ranging between 100s-300s in exposure time. We detect the OT identified by MASTER (Lipunov et al.) at: 03h 37m 44.97s +72d 31m 59.0s. Our estimated magnitudes are: R = 16.49 +/- 0.06 B = 17.11 +/- 0.11 These magnitudes are not corrected for Galactic extinction in the direction of the OT. Further observations are ongoing in conjunction with our own transient search of the LIGO/Virgo bayestar-HLV skymap. -- The Open University is incorporated by Royal Charter (RC 000391), an exempt charity in England & Wales and a charity registered in Scotland (SC 038302). The Open University is authorised and regulated by the Financial Conduct Authority in relation to its secondary activity of credit broking.