W Большой Медведицы
In the past the inner pair, designated component A, has been described as an eclipsing binary system, showing a primary minimum of 6.05 and a secondary minimum of 6.04. They have an orbital period of 0.841658 days, zero eccentricity, and an inclination of 19 degrees. However, Bruno Cester argued that the apparent eclipses are not real, and were caused by seeing different portions of distorted-shaped stars in a near contact binary system. As of 2017, it is classified as a rotating ellipsoidal variable and possibly a W Ursae Majoris-type system, although not in physical contact. The components of this pair appear to be equal, with stellar classifications of F0 V or F0 IV.