Zeta Gruis, Latinised from ζ Gruis, is a solitary[7] star in the southern constellation of Grus. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.12.[2] Based upon an annual parallax shift of 24.5 mas as seen from the Earth,[1] the system is located about 133 light-years from the Sun.
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Grus |
| Right ascension | 23h 00m 52.79777s[1] |
| Declination | −52° 45′ 14.8705″[1] |
| Apparent magnitude (V) | 4.12[2] |
| Characteristics | |
| Spectral type | K1 III Fe−1.2 CN−0.5[3] |
| U−B color index | +0.722[2] |
| B−V color index | +0.967[2] |
| Astrometry | |
| Radial velocity (Rv) | −1.1±2.7[4] km/s |
| Proper motion (μ) | RA: −57.911[1] mas/yr Dec.: −13.371[1] mas/yr |
| Parallax (π) | 24.5452 ± 0.5124 mas[1] |
| Distance | 133 ± 3 ly (40.7 ± 0.9 pc) |
| Absolute magnitude (MV) | +1.49[5] |
| Details | |
| Radius | 9.86+0.32 −0.65[1] R☉ |
| Luminosity | 45.6±1.1[1] L☉ |
| Temperature | 4,778+166 −75[1] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an evolved K-type giant star with a stellar classification of K1 III Fe−1.2 CN−0.5,[3] where the suffix notation indicates underabundances of iron and cyanogen in the spectrum. Having exhausted the supply of hydrogen at its core, the star has expanded and cooled; at present it has 10[1] times the girth of the Sun. The star is radiating 46[1] times the luminosity of the Sun from its swollen photosphere at an effective temperature of 4,778 K.[1]
References
edit- ^ a b c d e f g h i j k l 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 Jennens, P. A.; Helfer, H. L. (September 1975), "A new photometric metal abundance and luminosity calibration for field G and K giants", Monthly Notices of the Royal Astronomical Society, 172 (3): 667–679, Bibcode:1975MNRAS.172..667J, doi:10.1093/mnras/172.3.667.
- ^ a b Gray, R. O.; et al. (2006), "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample", The Astronomical Journal, 132 (1): 161–70, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637, S2CID 119476992.
- ^ Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system", Astronomy Letters, 32 (11): 759–771, arXiv:1606.08053, Bibcode:2006AstL...32..759G, doi:10.1134/S1063773706110065, S2CID 119231169.
- ^ 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.
- ^ "zet Gru". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-06-28.
- ^ 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.