HD 193721

HD 193721 is an astrometric binary in the southern circumpolar constellation Octans. It has an apparent magnitude of 5.77, allowing it to be faintly seen with the naked eye. Parallax measurements place the system 760 light years away from the Solar System and it is currently receding with a heliocentric radial velocity.
HD 193721 has a stellar classification of G6/8 II — intermediate between a G6 and 8 bright giant. At present it has 3.49 times the mass of the Sun, but has expanded to 24.4 times its girth. It shines with a luminosity of from its enlarged photosphere at an effective temperature of, giving a yellow hue. HD 193721 is metal deficient with an iron abundance 71% that of the Sun and spins leisurely with a projected [rotational velocity] of.
The system has a companion designated CPD −81°900. The object has a spectral classification of F8 and is located along a position angle of . CPD −81°900 is a foreground object, having a higher parallax and different proper motion.