46 Boötis

46 Boötis is a binary star system in the northern constellation of Boötes, located mid-way between α Coronae Borealis and ε Boötis. It has the Bayer designation b Boötis; 46 Boötis is the Flamsteed designation. The system lies 478 light-years away from the Sun based on parallax, and is visible to the naked eye as a faint, orange-hued star with a combined apparent visual magnitude of 5.67. It is moving away from the Earth with a heliocentric radial velocity of +19 km/s. The light from this system displays an unusually high level of polarization due to interstellar dust.

This is a single-lined spectroscopic binary with an orbital period of 2567.1 d and a large eccentricity of 0.83. The primary member, designated component A, is an aging giant star with a stellar classification of K2 III. As a consequence of exhausting the hydrogen at its core, it has expanded to 23 times the Sun's radius. It is radiating 176 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of $1.24$. The companion star, component B, is most likely a lower main-sequence star with 0.6–0.8 times the Sun's mass.