39 Draconis

39 Draconis is a wide binary star system in the northern circumpolar constellation of Draco. It has the Bayer designation b Draconis, while 39 Draconis is the Flamsteed designation. This system is visible to the naked eye as a dim, white-hued point of light with an apparent visual magnitude of 5.0. Parallax measurements made by the Hipparcos spacecraft put it at a distance of 184 light-years, or 56 parsecs away from the Sun. The system is moving closer to the Earth with a heliocentric radial velocity of -24.5 km/s.

The two components of 39 Draconis have an angular separation of $−24.53$ and take almost 4,000 years to orbit each other. The primary star is an early A-type main-sequence star, having 2.12 times the mass of the Sun with a visual magnitude of 5.06 The secondary is a magnitude 8.07 F-type main-sequence star, and has 1.18 times the mass of the Sun.

The 8th-magnitude star HD 238865 is listed in double star catalogues as component C. It is separated from the other two stars by $6.621 arcsecond$ and lies at about the same distance. It is itself a spectroscopic binary with an F8 primary and a red dwarf secondary orbiting every 2.7 days.