Observation data Epoch J2000 Equinox J2000 |
|
---|---|
Constellation | Ara |
Right ascension | 17h 50m 28.39341s |
Declination | –53° 36′ 44.6701″ |
Apparent magnitude (V) | 5.62 |
Characteristics | |
Spectral type | B2 V + B3 V + A1 V |
U−B color index | –0.64 |
B−V color index | –0.08 |
Variable type | Algol variable |
Astrometry | |
Radial velocity (Rv) | -8 km/s |
Proper motion (μ) |
RA: +3.18 mas/yr Dec.: –11.40 mas/yr |
Parallax (π) | 3.30 ± 0.47mas |
Distance | approx. 1,000 ly (approx. 300 pc) |
Absolute magnitude (MV) | –1.83/–1.11 |
Details | |
ν1 Ara A | |
Mass | 6.240 ± 0.066 M☉ |
Radius | 4.516 ± 0.084 R☉ |
Luminosity | 1,963 L☉ |
Surface gravity (log g) | 3.924 ± 0.016 cgs |
Temperature | 18100 ± 500 K |
Rotational velocity (v sin i) | 100 km/s |
Age | 23.2 ± 2.9 Myr |
ν1 Ara B | |
Mass | 5.314 ± 0.060 M☉ |
Radius | 3.428 ± 0.083 R☉ |
Luminosity | 902 L☉ |
Surface gravity (log g) | 4.093 ± 0.021 cgs |
Temperature | 17100 ± 500 K |
Rotational velocity (v sin i) | 130 km/s |
Other designations | |
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.