The location of V539 Arae (circled) | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Ara |
| Right ascension | 17 50 28.39341 |
| 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 ± 0.47 mas |
| Distance | approx. 1,000 ly (approx. 300 pc) |
| Absolute magnitude (MV) | –1.83/–1.11 |
| Details | |
| ν 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 | 18,100 ± 500 K |
| Rotational velocity (v sin i) | 100 km/s |
| Age | 23.2 ± 2.9 Myr |
| ν 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 | 17,100 ± 500 K |
| Rotational velocity (v sin i) | 130 km/s |
| Other designations | |
| V539 Ara, CD−53° 7423, HD 161783, HIP 87314, HR 6622, SAO 245065. | |
| Database references | |
| SIMBAD | AB |
| A | |
V539 Arae (Bayer designation Nu Arae (ν Arae / ν Ara)) is a triple star system in the southern constellation of Ara. It is a variable star, the brightness of which varies from magnitude 5.71 to 6.24, making it faintly visible to the naked eye under good observing conditions. 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.
In 1930, Ferdinand Johannes Neubauer found that the star (usually called Boss 4496 at the time) is a spectroscopic binary. He did not detect any brightness variability. Eclipses were first reported by E. Schoeffel and U. Kohler in 1965. The period they reported is 1/2 the currently accepted value, because they did not realize that the light curve has a deep secondary minimum.
The core members of this system, ν 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 Upsilon Arae (υ Arae), and more generally unlettered.
References
- ^ van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
- ^ Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- ^ Wilson, Ralph Elmer (1953), "General catalogue of stellar radial velocities", Carnegie Institute Washington D.C. Publication, Carnegie Institution of Washington, Bibcode:1953GCRV..C......0W.
- ^ Torres, G.; Andersen, J.; Giménez, A. (February 2010), "Accurate masses and radii of normal stars: modern results and applications", The Astronomy and Astrophysics Review, 18 (1–2): 67–126, arXiv:0908.2624, Bibcode:2010A&ARv..18...67T, doi:10.1007/s00159-009-0025-1, S2CID 14006009.
- Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410 (1): 190–200, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x, S2CID 118629873.
- ^ "V* V539 Ara". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2010-07-31.
- Samus, N. N.; Goranskij, V. P.; Durlevich, O. V.; Kazarovets, E. V.; Kireeva, N. N.; Pastukhova, E. N.; Zharova, A. V. "V539 Ara". General Catalogue of Variable Stars. Lomonosov Moscow State University. Retrieved 25 November 2024.
- Knipe, G. F. G. (September 1971). "The light curve and orbital elements of V539 Arae". Astronomy & Astrophysics. 14: 70–77. Bibcode:1971A&A....14...70K. Retrieved 25 October 2021.
- Neubauer, F. J. (August 1930). "Forty-two Spectroscopic Binary Stars". Publications of the Astronomical Society of the Pacific. 42 (248): 235–236. Bibcode:1930PASP...42..235N. doi:10.1086/124043. Retrieved 25 November 2024.
- Schoeffel, E.; Kohler, U. (January 1965). "Photometric Light-Curves of Bright Southern BV-Stars Eclipsing Binaries". Information Bulletin on Variable Stars. 77. Bibcode:1965IBVS...77....1S. Retrieved 25 November 2024.
- Thackeray, A. D.; Knipe, G. F. G. (1965). "The Eclipsing Variable HD 161783 (BV 420)". Monthly Notes of the Astron. Soc. Southern Africa. 24. Bibcode:1965MNSSA..24..109T. Retrieved 25 November 2024.
- Malkov, O. Yu.; Oblak, E.; Snegireva, E. A.; Torra, J. (February 2006), "A catalogue of eclipsing variables", Astronomy and Astrophysics, 446 (2): 785–789, Bibcode:2006A&A...446..785M, doi:10.1051/0004-6361:20053137, hdl:10995/73280.
- Note for HR 6622: Hoffleit, D., Warren, Jr., W. H., (1991). The Bright Star Catalogue, (5th Revised Ed).
External links
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