23 Comae Berenices

23 Comae Berenices is a binary star system in the northern constellation of Coma Berenices, situated a few degrees away from the North Galactic Pole. It is visible to the naked eye as a faint, white-hued point of light with an apparent visual magnitude of 4.80. The system is located around 310 light years away from the Sun, based on parallax. It is moving closer to the Earth with a heliocentric radial velocity of −16 km/s.

The components of this system orbit each other with a period of 33 years, a large eccentricity of 0.9, and an angular semimajor axis of $0.012$. The primary, designated component A, is a magnitude 4.96 star with a stellar classification of A0IV, matching an A-type subgiant that has exhausted the supply of hydrogen at its core and is in the process of evolving into a giant. Bychkov et al. (2009) list it as an Am star with an average field strength of $−16.0$.

The primary is 210 million years old and is spinning with a projected rotational velocity of 40 km/s. It has 2.15 times the mass of the Sun and about three times the Sun's radius. The star is radiating 104 times the luminosity of the Sun from its photosphere at an effective temperature of 9,675 K.