TITLE: GCN CIRCULAR NUMBER: 23267 SUBJECT: GRB 180924A: MASTER inspection DATE: 18/09/25 09:29:21 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, D. Vlasenko, N.Tiurina, V.Kornilov, A.Kuznetsov, V.Chazov, I. Gorbunov, D.Zimnukhov, D.Kuvshinov, P.Balanutsa, V.Vladimirov, Lomonosov Moscow State University,SAI A. Tlatov, V.Senik, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory D. Buckley, South African Astronomical Observatory (SAAO) R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias (IAC) R. Podesta, F. Podesta, C. Lopez, C.Francile Observatorio Astronomico Felix Aguilar (OAFA) H.Levato, Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) O. Gres, N.M.Budnev , Yu.Ishmuhametova Irkutsk State University (ISU) A. Gabovich, V. Yurkov, Yu. Sergienko Blagoveschensk Educational State University (BSPU) MASTER-OAFA robotic telescope (MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to Swift GRB 180924A (Ukwatta et al. GCN 23261, Evans et al. GCN 23262, Stamatikos et al. GCN 23264, Melandri et al. GCN 23266) 57128 sec after notice time and 57128 sec after trigger time at 2018-09-25 07:14:30 UT. There is no new astrophysical sources detected brighter then 19.3m (unfiltered) inside Swift XRT error-box (03h 16m 47.87s -58d 31' 57.3", r=1.7arcsec Evans et al. GCN 23262) The message may be cited. ==================================================================== The galacitc latitude b = -49.7 deg. The observations made on zenit distance = 27 deg. The moon (99.8 % bright part) was 40 deg. above the horizon. The distance between moon and object is 66 The sun altitude was -35.5 deg.