Astronomy:Gamma1 Fornacis

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Short description: Star in the constellation Fornax


γ1 Fornacis
Fornax constellation map.svg
Red circle.svg
Location of γ1 Fornacis (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Fornax
Right ascension  02h 49m 50.96219s[1]
Declination −24° 33′ 37.1290″[1]
Apparent magnitude (V) 6.154[2]
Characteristics
Spectral type G9 III[3]
B−V color index 1.081[2]
Astrometry
Radial velocity (Rv)−6.58±0.64[4] km/s
Proper motion (μ) RA: −51.603[1] mas/yr
Dec.: −127.797[1] mas/yr
Parallax (π)8.8835 ± 0.0576[1] mas
Distance367 ± 2 ly
(112.6 ± 0.7 pc)
Absolute magnitude (MV)+0.52±0.21[4]
Details
Mass1.65[2] M
Radius10.44+0.73
−0.49
[1] R
Luminosity50.814±0.439[1] L
Surface gravity (log g)2.60[4] cgs
Temperature4,657±56[2] K
Metallicity [Fe/H]−0.02[4] dex
Age3.36[2] Gyr
Other designations
γ1 For, CD−25°1120, GC 3404, HD 17713, HIP 13197, HR 844, SAO 168081, WDS J02498-2434A[5]
Database references
SIMBADdata

Gamma1 Fornacis, which is Latinized from γ1 Fornacis, is a star in the constellation Fornax, positioned less than a degree south of the border with Eridanus.[6] The star has a golden hue and can be a challenge to view with the naked eye even in good seeing conditions, having an apparent visual magnitude of 6.15.[2] It is located at a distance of approximately 367 light years from the Sun based on parallax,[1] but is drifting closer with a radial velocity of −7 km/s.[4] The star has an absolute magnitude of +0.5.[4]

The stellar classification of γ1 Fornacis is G9 III,[3] which indicates this is an aging giant star[4] that has exhausted the supply of hydrogen at its core, then cooled and expanded away from the main sequence. It is an estimated 3.4[2] billion years old with a metallicity that is close to solar, indicating the abundances of heavy elements are similar to those in the Sun. It has 1.65[2] times the mass of the Sun and has expanded to ten[1] times the Sun's radius. The star is radiating 51[1] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,657 K.[2]

γ1 Fornacis has three visual companions listed in the Washington Double Star Catalog. These are faint 11th - 13th magnitude stars at 11' - 56' distance from γ1.[7] Gamma2 Fornacis is a 5th magnitude star located four degrees to the south.[6]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 Luck, R. Earle (2015). "Abundances in the Local Region. I. G and K Giants". Astronomical Journal 150 (3): 88. doi:10.1088/0004-6256/150/3/88. Bibcode2015AJ....150...88L. 
  3. 3.0 3.1 Abt, Helmut A. (2008). "Visual Multiples. IX. MK Spectral Types". The Astrophysical Journal Supplement Series 176: 216–217. doi:10.1086/525529. Bibcode2008ApJS..176..216A. 
  4. 4.0 4.1 4.2 4.3 4.4 4.5 4.6 Luck, R. Earle; Heiter, Ulrike (2007). "Giants in the Local Region". The Astronomical Journal 133 (6): 2464. doi:10.1086/513194. Bibcode2007AJ....133.2464L. 
  5. "gam01 For". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=gam01+For. 
  6. 6.0 6.1 Sinnott, Roger W.; Perryman, Michael A. C. (1997). Millennium Star Atlas. 1. Sky Publishing Corporation and the European Space Agency. pp. 358, 381. ISBN 0-933346-84-0. 
  7. Mason, Brian D. et al. (2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal 122 (6): 3466. doi:10.1086/323920. Bibcode2001AJ....122.3466M.