27 Arietis
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Aries |
| Right ascension | 02h 30m 54.39715s[1] |
| Declination | +17° 42′ 13.8908″[1] |
| Apparent magnitude (V) | 6.21[2] |
| Characteristics | |
| Spectral type | G8 III-IV Fe-2[3] |
| B−V color index | 0.908±0.002[2] |
| Astrometry | |
| Radial velocity (Rv) | −122.71±0.28[2] km/s |
| Proper motion (μ) | RA: +33.774[1] mas/yr Dec.: −82.912[1] mas/yr |
| Parallax (π) | 11.6403 ± 0.1172 mas[1] |
| Distance | 280 ± 3 ly (85.9 ± 0.9 pc) |
| Absolute magnitude (MV) | 1.48[2] |
| Orbit[4] | |
| Period (P) | 130.706±0.008 d |
| Eccentricity (e) | 0.366±0.007 |
| Periastron epoch (T) | 53,480.1±0.4 MJD |
| Argument of periastron (ω) (secondary) | 275.5±0.7° |
| Semi-amplitude (K1) (primary) | 5.98±0.05 km/s |
| Details | |
| Mass | 1.29[5] M☉ |
| Radius | 7.04+0.29 −0.28 R☉ |
| Luminosity | 28.43[2] L☉ |
| Surface gravity (log g) | 2.77±0.21[6] cgs |
| Temperature | 4,788±49[5] K |
| Metallicity [Fe/H] | −0.65±0.02[2] dex |
| Rotational velocity (v sin i) | 1.6[4] km/s |
| Age | 5.44[5] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
27 Arietis is a binary star[4] system in the northern constellation of Aries. 27 Arietis is the Flamsteed designation. It is a dim, yellow-hued star that is close to the lower limit of what can be viewed with the naked eye, having an apparent visual magnitude is 6.21.[2] The annual parallax shift of 11.64±0.12 mas[1] corresponds to a physical distance of approximately 280 light-years (86 parsecs) from Earth. It is advancing closer to the Earth with a heliocentric radial velocity of −122.7 km/s, and may come as close as 84 light-years in around 643,000 years.[2]
This appears to be a single-lined spectroscopic binary system with an orbital period of 130.7 days and an eccentricity of 0.366. It has an "a sin i" value of 10.00 ± 0.08 Gm (0.06685 ± 0.00053 AU), where a is the semimajor axis and i is the inclination to the line of sight from the Earth. This value provides a lower bound on the actual semimajor axis.[4] The visible component has a stellar classification of G8 III-IV Fe-2,[3] displaying mixed spectral traits of an evolved subgiant and a giant star, with a strong underabundance of iron. The CN bands of this star are very weak.[4]
References
[edit]- ^ a b c d e f 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 d e f g h 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 Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373.
- ^ a b c d e Griffin, R. F. (October 2011), "Spectroscopic binary orbits from photoelectric radial velocities - Paper 220: 60 Piscium, 27 Arietis, EZ Ursae Majoris, and 4 Equulei", The Observatory, 131 (5): 294–314, Bibcode:2011Obs...131..294G.
- ^ a b c Luck, R. Earle (2015), "Abundances in the Local Region. I. G and K Giants", Astronomical Journal, 150 (3), 88, arXiv:1507.01466, Bibcode:2015AJ....150...88L, doi:10.1088/0004-6256/150/3/88, S2CID 118505114.
- ^ Prugniel, P.; et al. (2011), "The atmospheric parameters and spectral interpolator for the MILES stars", Astronomy & Astrophysics, 531: A165, arXiv:1104.4952, Bibcode:2011A&A...531A.165P, doi:10.1051/0004-6361/201116769, S2CID 54940439.
- ^ "27 Ari". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-06-02.
