The brightest component, a blue supergiant designated Mu Sagittarii Aa, is formally named Polis /ˈpɒlɪs/.
Component D has also been listed as a purely optical double by some authors,[7] but others consider it to be part of a trapezium system of four gravitationally bound stars (plus an unseen companion).
Consequently, the Chinese name for Mu Sagittarii itself is 斗宿三 (Dǒu Sù sān, English: the Third Star of Dipper.
The apparent magnitude for component B has been measured at between +8.04[5] and 10.481,[21] leading to uncertainties about its physical properties, distance, and membership of the system.
[24] The full MK spectral type has been measured as B2 IV, and the assumption of a subgiant luminosity suggests that it is more distant than the other stars of the system.