HD 129132
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Boötes |
| Right ascension | 19h 40m 05.79185s[1] |
| Declination | +18° 00′ 50.0046″[1] |
| Apparent magnitude (V) | 6.13[2] |
| Characteristics | |
| Spectral type | G0V[3] or F4III[4] |
| B−V color index | 0.434±0.004[2] |
| Astrometry | |
| Radial velocity (Rv) | +1.667±0.0024[1] km/s |
| Proper motion (μ) | RA: +14.630[1] mas/yr Dec.: −20.160[1] mas/yr |
| Parallax (π) | 8.5307 ± 0.1848 mas[1] |
| Distance | 382 ± 8 ly (117 ± 3 pc) |
| Absolute magnitude (MV) | 0.82 |
| Orbit[5] | |
| Primary | A |
| Companion | B |
| Period (P) | 101.606±0.003 d |
| Semi-major axis (a) | ≥26.4±0.2 Gm |
| Eccentricity (e) | 0.117±0.007 |
| Periastron epoch (T) | 2,442,478.0±0.8 HJD |
| Semi-amplitude (K1) (primary) | 19.0±0.1 km/s |
| Orbit[5] | |
| Primary | AB |
| Companion | C |
| Period (P) | 3,385±7 d |
| Semi-major axis (a) | 0.074±0.001" (407±6 Gm) |
| Eccentricity (e) | 0.073±0.010 |
| Inclination (i) | 104.6±0.5° |
| Periastron epoch (T) | 2,442,880±40 HJD |
| Argument of periastron (ω) (secondary) | 91.4±4.1° |
| Semi-amplitude (K1) (primary) | 8.5±0.1 km/s |
| Details | |
| A | |
| Mass | 1.99[6] M☉ |
| Radius | 17.0+1.7 −1.6[1] R☉ |
| Luminosity | 236.1+5.9 −5.7[1] L☉ |
| Surface gravity (log g) | 3.41[6] cgs |
| Temperature | 5,488+275 −258[1] K |
| Rotational velocity (v sin i) | 25.3[6] km/s |
| Age | 1.00[6] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 129132 is a triple star[5] system in the northern constellation of Boötes. It is dimly visible to the naked eye with a combined apparent visual magnitude of 6.13.[2] The distance to this system is approximately 382 light years based on parallax, and it is drifting further away from the Sun with a radial velocity of +1.7 km/s.[1]
This system was found to be a spectroscopic binary by the Dominion Astrophysical Observatory in 1923. It was then shown to be a triple star system in 1937 by William E. Harper and Guy H. Blanchet.[8] The inner pair have an orbital period of 101.6 days and an eccentricity of 0.117, with the primary forming the visible component of this pair. The third component forms a visual system with the inner pair, orbiting with a period of 9.27 years and an eccentricity of 0.073.[5][9]
The primary component appears to be an aging giant star with a stellar classification of F4III,[4] although it has also been classed as a G-type main-sequence star of type G0V.[3] It is around a billion years old with twice the mass of the Sun.[6] The star has expanded to 17[1] times the Sun's radius and is radiating 236[1] times the luminosity of the Sun at an effective temperature of 5,488 K.[1] It is spinning with a projected rotational velocity of 25.3 km/s.[6]
References
[edit]- ^ a b c d e f g h i j k l m Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
- ^ a b Harlan, E. A.; Taylor, D. C. (March 1970). "MK classifications for F- and G-type stars. II". Astronomical Journal. 75 (2): 165–166. Bibcode:1970AJ.....75..165H. doi:10.1086/110956.
- ^ a b Cowley, A. P.; Bidelman, W. P. (February 1979). "MK spectral types for some F and G stars". Publications of the Astronomical Society of the Pacific. 91: 83–86. Bibcode:1979PASP...91...83C. doi:10.1086/130446.
- ^ a b c d Barlow, D. J.; Scarfe, C. D. (December 1991). "The Spectroscopic-Speckle Triple System HR 5472". Astronomical Journal. 102: 2098. Bibcode:1991AJ....102.2098B. doi:10.1086/116034.
- ^ a b c d e f Luck, R. Earle (January 2017). "Abundances in the Local Region II: F, G, and K Dwarfs and Subgiants". The Astronomical Journal. 153 (1): 19. arXiv:1611.02897. Bibcode:2017AJ....153...21L. doi:10.3847/1538-3881/153/1/21. S2CID 119511744. 21.
- ^ "HD 129132". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-02-03.
- ^ Harper, W. E.; Blanchet, G. H. (July 1937). "The spectroscopic orbits of H. R. 5472". Publications of the Dominion Observatory Ottawa. 7: 99-104. Bibcode:1937PDAO....7...99H.
- ^ Malkov, O. Yu.; Tamazian, V. S.; Docobo, J. A.; Chulkov, D. A. (2012). "Dynamical Masses of a Selected Sample of Orbital Binaries". Astronomy & Astrophysics. 546: 5. Bibcode:2012A&A...546A..69M. doi:10.1051/0004-6361/201219774. A69.
