STF 1196 (Zeta Cancri) is a 5-star system located 82 light-years away. It consists of the binary system Zeta1 Cancri (AB) and the trinary system Zeta2 Cancri (C). Both components of Zeta1 Cancri are yellow-white main sequence stars of spectral types F7V and F9V, with masses of 1.28 and 1.18 times that of the Sun. They orbit around their common center of mass with a period of 59 years. Zeta2 Cancri is a trinary system, where the primary component is a yellow main sequence star of spectral type G0V, with a mass of 1.15 and a radius of 1.27 times that of the Sun. Its companion is a very tight pair of red dwarfs. The primary star and the red dwarf pair are separated by 0.3", with an orbital period of 17 years. The orbital period of the Zeta1 and Zeta2 components is estimated to be 735 years.

100mm: Given the separation between the components AB, which is only 1.1", I expected that I would see AB at best as an elongation or that the components would remain connected. After focusing at 225x, I was very surprised at how easily I could distinguish this tight binary Zeta1. Not just as a hint, but with a clearly visible thin dark gap between the components. The similar brightness of the stars, very good observing conditions, and the position of the observed stars definitely helped. In terms of color, I observed components A and B as light yellow and component C as dark yellow.