Luminosity 902 L☉ Apparent magnitude (V) 5.62 Radial velocity (Rv) -8 km/s | Magnitude 5.62 Absolute magnitude (MV) –1.83/–1.11 B−V color index –0.08 | |
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Distance approx. 1,000 ly; (approx. 300 pc) | ||
V539 Arae (Bayer designation Nu1 Arae (ν1 Arae / ν1 Ara)) is a triple star system in the southern constellation of Ara. Based upon an annual parallax shift of 3.30 ± 0.47, this system is at a distance of roughly 1,000 light-years (310 parsecs) from Earth.
The core members of this system, ν1 Ara AB, consist of a pair of B-type main sequence stars in a close orbit with a period of 3.169 days and an eccentricity of 0.06. Their respective stellar classifications are B2 V and B3 V, and they have a combined visual magnitude of 5.65. Because the orbital plane lies close to the line of sight from the Earth, this pair form a detached eclipsing binary of the Algol type. The eclipse of the primary causes a decrease of 0.52 in magnitude, while the secondary eclipse decreases the magnitude by 0.43. At an angular separation of 12.34 arcseconds, is the tertiary component of this system; a magnitude 9.40 A-type main sequence star with a classification of A1 V.
The system is sometimes referred as Upsilon1 Arae (υ1 Arae), and more generally unlettered.