Nu Gruis

Nu Gruis

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Grus
Right ascension	22^h 28^m 39.21034^s[1]
Declination	−39° 07′ 54.4505″[1]
Apparent magnitude (V)	5.47[2]
Characteristics
Spectral type	G9 III[3]
B−V color index	+0.95[2]
Astrometry
Radial velocity (Rv)	+10.6[4] km/s
Proper motion (μ)	RA: +37.43[5] mas/yr Dec.: −160.51[5] mas/yr
Parallax (π)	11.6404 ± 0.1235 mas[1]
Distance	280 ± 3 ly (85.9 ± 0.9 pc)
Absolute magnitude (MV)	+0.76[6]
Details
Radius	9.68+0.30 −0.26[1] R☉
Luminosity	51.9+0.3 −0.7[1] L☉
Surface gravity (log g)	2.63±0.08[7] cgs
Temperature	4,893±24[7] K
Metallicity [Fe/H]	−0.41±0.02[7] dex
Other designations
ν Gru, CD−39° 14723, FK5 845, HD 212953, HIP 110936, HR 8552, SAO 213850, WDS J22287-3908[8]
Database references
SIMBAD	data

ν Gruis, Latinised as Nu Gruis, is a solitary,^[9] yellow-hued star in the southern constellation of Grus. It is visible to the naked eye with an apparent visual magnitude of 5.47.^[2] The distance to this star, as determined using an annual parallax shift of 11.6 mas as seen from the Earth,^[1] is 280 light years. It is drifting further away with a heliocentric radial velocity of +11 km/s.^[4]

This is an evolved G-type giant star with a stellar classification of G9 III,^[3] a star that has used up its core hydrogen and has expanded. At present it has ten^[1] times the radius of the Sun and is radiating 52^[1] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,893 K.^[7] It has a visual magnitude 12.50 companion, not visible even through binoculars, located at an angular separation of 21.70 arc seconds along a position angle of 74°, as of 2011.^[10]

References

1. 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.
2. Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (99): 99, Bibcode:1966CoLPL...4...99J.
3. Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1982mcts.book.....H.
4. Wilson, R. E. (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication, Carnegie Institute of Washington, D.C., Bibcode:1953GCRV..C......0W.
5. 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.
6. 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.
7. Alves, S.; et al. (April 2015), "Determination of the spectroscopic stellar parameters for 257 field giant stars", Monthly Notices of the Royal Astronomical Society, 448 (3): 2749–2765, arXiv:1503.02556, Bibcode:2015MNRAS.448.2749A, doi:10.1093/mnras/stv189.
8. "nu. Gru -- Star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2017-06-26.
9. 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.
10. 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.