Astronomy:Beta Fornacis

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Short description: Star in the constellation Fornax
β Fornacis
Observation data
Equinox J2000.0]] (ICRS)
Constellation Fornax
Right ascension  02h 49m 05.41890s[1]
Declination −32° 24′ 21.2320″[1]
Apparent magnitude (V) 4.46[2]
Characteristics
Evolutionary stage red clump[3][4]
Spectral type G8 III[5]
U−B color index +0.69[2]
B−V color index +0.99[2]
R−I color index +0.54
Astrometry
Radial velocity (Rv)+17.56±0.12[1] km/s
Proper motion (μ) RA: +86.023[1] mas/yr
Dec.: +159.404[1] mas/yr
Parallax (π)18.4596 ± 0.1024[1] mas
Distance176.7 ± 1.0 ly
(54.2 ± 0.3 pc)
Absolute magnitude (MV)0.894[4]
Details[6]
Mass1.33±0.01 M
Radius10.45±0.07 R
Luminosity51.3±0.7 L
Surface gravity (log g)2.67±0.10 cgs
Temperature4,790±50 K
Metallicity [Fe/H]−0.34±0.10 dex
Rotational velocity (v sin i)2.19[7] km/s
Age3.27±0.02 Gyr
Other designations
β For, CD−32°1025, FK5 101, HD 17652, HIP 13147, HR 841, NLTT 9066, SAO 193931, WDS 02491-3224A[8]
Database references
SIMBADdata

Beta Fornacis (Beta For, β Fornacis, β For) is solitary[9] 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 18.46 mas,[1] it is located around 177 light years away from the Sun. At that distance, the visual magnitude is reduced by an interstellar extinction factor of 0.1.[7]

This is an evolved, G-type giant star with a stellar classification of G8 III.[5] 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.[3][4] Beta Fornacis has 1.33 times the mass of the Sun and, at an age of 3.3 billion years, has expanded to 10.5 times the Sun's radius. It is radiating 51 times the solar luminosity from its outer atmosphere at an effective temperature of 4,790 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]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  2. 2.0 2.1 2.2 2.3 Johnson, H. L. et al. (1999), "UBVRIJKL photometry of the bright stars", Commission Lunar and Planetary Laboratory 4: 99, Bibcode1966CoLPL...4...99J. 
  3. 3.0 3.1 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, Bibcode2002AcA....52..159K. 
  4. 4.0 4.1 4.2 Liu, Y. J. et al. (2007), "The abundances of nearby red clump giants", Monthly Notices of the Royal Astronomical Society 382 (2): 553–66, doi:10.1111/j.1365-2966.2007.11852.x, Bibcode2007MNRAS.382..553L. 
  5. 5.0 5.1 Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode1982mcts.book.....H. 
  6. 6.0 6.1 Gallenne, A.; Pietrzyński, G.; Graczyk, D.; Nardetto, N.; Mérand, A.; Kervella, P.; Gieren, W.; Villanova, S. et al. (2018-08-01), "Fundamental properties of red-clump stars from long-baseline H-band interferometry" (in en), Astronomy & Astrophysics 616: A68, doi:10.1051/0004-6361/201833341, ISSN 0004-6361, Bibcode2018A&A...616A..68G. 
  7. 7.0 7.1 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, doi:10.1051/0004-6361/201117887, Bibcode2011A&A...536A..71J. 
  8. "* bet For". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=%2A+bet+For. 
  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, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode2008MNRAS.389..869E. 
  10. Mason, B. D. et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal 122 (6): 3466–3471, doi:10.1086/323920, Bibcode2001AJ....122.3466M. 
  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 978-0387716091, https://books.google.com/books?id=f42fFDCTF0MC&pg=PA617.