Beta Fornacis

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β Fornacis
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Fornax
Right ascension 02h 49m 05.41885s[1]
Declination −32° 24′ 21.2319″[1]
Apparent magnitude (V) 4.46[2]
Spectral type G8 III[3]
U−B color index +0.69[2]
B−V color index +0.99[2]
R−I color index +0.54
Radial velocity (Rv) +16.8[4] km/s
Proper motion (μ) RA: +86.01[1] mas/yr
Dec.: +158.81[1] mas/yr
Parallax (π) 18.89 ± 0.26[1] mas
Distance 173 ± 2 ly
(52.9 ± 0.7 pc)
Absolute magnitude (MV) 0.894[5]
Mass 1.53 M
Radius 11.02 R
Luminosity 55.8 L
Surface gravity (log g) 2.45 cgs
Temperature 4,820 K
Metallicity [Fe/H] −0.37±0.08 dex
Rotational velocity (v sin i) 2.19 km/s
Other designations
β For, CD−32° 1025, FK5 101, HD 17652, HIP 13147, HR 841, NLTT 9066, SAO 193931, WDS 02491-3224A.[7]
Database references

Beta Fornacis (Beta For, β Fornacis, β For) is the Bayer designation for a solitary[8] star in the southern constellation of Fornax. It is visible to the naked eye with an apparent visual magnitude of 4.46.[2] Based upon an annual parallax shift of 18.89 mas,[1] it is located around 173 light years away from the Sun. At that distance, the visual magnitude is reduced by an interstellar extinction factor of 0.1.[6]

This is an evolved, G-type giant star with a stellar classification of G8 III.[3] It is a red clump giant, which means it has undergone helium flash and is currently generating energy through the fusion of helium at its core.[9][5] The star has an estimated 1.53 times the mass of the Sun and has expanded to 11 times the Sun's radius. It is radiating over 55 times the solar luminosity from its outer atmosphere at an effective temperature of 4,820 K.[6]

Beta Fornacis has a visual companion, CCDM J02491-3224B, which has an apparent visual magnitude of approximately 14.0. As of 1928, it lay at an angular separation of 4.80 arc seconds along a position angle of 67°.[10] Located around three degrees to the southwest is the globular cluster NGC 1049.[11]


  1. ^ a b c d e f van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752Freely accessible, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357. 
  2. ^ a b c d Johnson, H. L.; et al. (1999), "UBVRIJKL photometry of the bright stars", Commission Lunar and Planetary Laboratory, 4: 99, Bibcode:1966CoLPL...4...99J. 
  3. ^ a b Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1982MSS...C03....0H. 
  4. ^ Wilson, Ralph Elmer (1953), General Catalogue of Stellar Radial Velocities, Washington: Carnegie Institution of Washington, Bibcode:1953GCRV..C......0W. 
  5. ^ a b 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. 
  6. ^ a b c Jones, M. I.; et al. (2011), "Study of the impact of the post-MS evolution of the host star on the orbits of close-in planets", Astronomy & Astrophysics, 536: A71, arXiv:1110.6459Freely accessible, Bibcode:2011A&A...536A..71J, doi:10.1051/0004-6361/201117887. 
  7. ^ "* bet For". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-01-21. 
  8. ^ 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:0806.2878Freely accessible, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x. 
  9. ^ Kubiak, M.; McWilliam, A.; Udalski, A.; Gorski, K. (June 2002), "Metal Abundance of Red Clump Stars in Baade's Window", Acta Astronomica, 52: 159−175, Bibcode:2002AcA....52..159K. 
  10. ^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122: 3466–3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920. 
  11. ^ Plotner, Tammy (2007), The Night Sky Companion: A Yearly Guide to Sky-Watching 2008-2009, The Patrick Moore Practical Astronomy Series, Springer Science & Business Media, p. 617, ISBN 0387716092.