Title: The contact binary GSC 04778-00152 with a visual companion Authors: T. Tuvikene (1), T. Eenmäe (2), C. Sterken (1), E. Brogt (3) ((1) Vrije Universiteit Brussel, (2) Tartu Observatory, (3) Steward Observatory, Department of Astronomy, The University of Arizona)
Photometric and spectroscopic observations of the unstudied 12th-magnitude eclipsing binary GSC 04778-00152 are presented. We report the discovery of a visual companion about 1 mag fainter and 2 arcsec away from the binary. By subtracting the light contribution of the visual companion, we obtain the UBVRI light curves of the binary system alone. The shape of the light curve indicates that GSC 04778-00152 is an A-type W UMa contact binary. From light-curve modelling, we derive parameters of the binary system.