Rho Gruis
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Grus |
| Right ascension | 22h 43m 29.97654s[1] |
| Declination | −41° 24′ 51.6467″[1] |
| Apparent magnitude (V) | 4.847[2] |
| Characteristics | |
| Evolutionary stage | horizontal branch[2] |
| Spectral type | K0 III[3] |
| U−B color index | +0.807[4] |
| B−V color index | +1.026[4] |
| Astrometry | |
| Radial velocity (Rv) | 30.89±0.15[5] km/s |
| Proper motion (μ) | RA: +10.11[1] mas/yr Dec.: −93.79[1] mas/yr |
| Parallax (π) | 14.16 ± 0.19 mas[1] |
| Distance | 230 ± 3 ly (70.6 ± 0.9 pc) |
| Absolute magnitude (MV) | 0.685[2] |
| Details | |
| Mass | 1.91[2] M☉ |
| Radius | 12.15+0.19 −0.65[5] R☉ |
| Luminosity | 66.9±1.3[5] L☉ |
| Surface gravity (log g) | 2.62[2] cgs |
| Temperature | 4736.67+131.83 −36.67[5] K |
| Metallicity [Fe/H] | −0.20[2] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
Rho Gruis, a Latinization of ρ 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 4.85.[2] Based upon an annual parallax shift of 14.16 mas as seen from the Earth,[1] the system is located about 230 light years from the Sun. It is drifting further away with a radial velocity of 31 km/s.[5]
This object is an evolved K-type giant star with a stellar classification of K0 III.[3] It has exhausted the supply of hydrogen at its core, causing it to cool and expand. At present it has 12[5] times the radius of the Sun. With 1.9 times the mass of the Sun[2] it is a red clump star,[2] which indicates it is on the horizontal branch generating energy through helium fusion at its core. It is radiating 67[5] times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,737 K.[5]
Rho Gruis has two visual companions: a magnitude 14.0 star at an angular separation of 19.3″ along a position angle (PA) of 302°, as of 2011, and a magnitude 10.28 star with a separation of 114.20″ and a PA of 336°, as of 1999.[8]
References
[edit]- ^ a b c d e f van Leeuwen, F. (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.
- ^ a b c d e f g h i Liu, Y. J.; et al. (2007), "The abundances of nearby red clump giants", Monthly Notices of the Royal Astronomical Society, 382 (2): 553–66, Bibcode:2007MNRAS.382..553L, doi:10.1111/j.1365-2966.2007.11852.x.
- ^ a b Houk, N. (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 2, Dept. of Astronomy, University of Michigan, Bibcode:1978mcts.book.....H.
- ^ a b Cousins, A. W. J. (1983), "UBV photometry of E region standard stars of intermediate brightness", South African Astronomical Observatory Circular, 7 (7): 36–46, Bibcode:1983SAAOC...7...36C.
- ^ a b c d e f g h 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.
- ^ "* rho Gru". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-06-24.
{{cite web}}: CS1 maint: postscript (link) - ^ 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.
- ^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122 (6): 3466, Bibcode:2001AJ....122.3466M, doi:10.1086/323920
