RS CVn type eclipsing binary MM Herculis have been observed using B, V, R filters in 1997 and obtained light and colour curves were examined together with the earlier 12 light and colour curves obtained between 1976 and 1997. It was seen that the system is bluer, while it is fainter. Such finding probably reveals the evolutionary effect of the photospheric bright facular structures surrounding starspots.
TAŞ, GÜNAY (1999) "The Light and Colour Variations of MM Her," Turkish Journal of Physics: Vol. 23: No. 2, Article 11. Available at: https://journals.tubitak.gov.tr/physics/vol23/iss2/11