V965 Cephei Revisited: Evidence for a Binary System

Volume 53 number 2 (2025)

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Maksym Pyatnytskyy

Private Observatory Osokorky, P. O. Box 27, Kyiv, 02132, Ukraine; pmak@osokorky-observatory.com

Abstract

We extended the O–C diagram of the HADS star V965 Cep with all currently available observations in the Johnson V filter and added unfiltered ones. The new, up-to-date O–C diagram shows that the seeming period change previously revealed by the author does not occur uniformly. Instead, the near-parabolic part of the O–C diagram can be a part of a periodic curve. This could be a sign of a second body in the system. Based on our observations, we also estimated the B–V index of the star to be 0.48 ± 0.05 at maximum brightness and 0.57 ± 0.05 at minimum brightness.