Astronomy:Epsilon Columbae

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Short description: Star in the constellation Columba
ε Columbae
Location of ε Columbae (circled in red)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Columba[1]
Right ascension  05h 31m 12.747s[2]
Declination −35° 28′ 13.82″[2]
Apparent magnitude (V) 3.87[3]
Characteristics
Spectral type K1 II/III[4] or K1 IIIa[5]
U−B color index +1.08[3]
B−V color index +1.14[3]
Astrometry
Radial velocity (Rv)−4.9±0.7[6] km/s
Proper motion (μ) RA: +27.627[2] mas/yr
Dec.: −32.416[2] mas/yr
Parallax (π)11.7300 ± 0.1374[2] mas
Distance278 ± 3 ly
(85.3 ± 1.0 pc)
Absolute magnitude (MV)−0.67[1]
Details
Mass2.47[7] M☉
Radius25.2+3.1
−2.0
[8] R☉
Luminosity251.2±5.6[8] L☉
Surface gravity (log g)1.76±0.10[9] cgs
Temperature4,573±50[9] K
Metallicity [Fe/H]−0.07±0.10[9] dex
Age1.53[7] Gyr
Other designations
ε Col, CD−35°2348, FK5 2413, HD 36597, HIP 25859, HR 1862, SAO 195924[10]
Database references
SIMBADdata

Epsilon Columbae is a star in the southern constellation of Columba. Its name is a Bayer designation that is Latinized from ε Columbae, and abbreviated Epsilon Col or ε Col. This star is visible to the naked eye, having an apparent visual magnitude of 3.87.[3] Based upon an annual parallax shift of 11.73 mas,[8] it is located approximately 278 light-years (85.3 pc) distant from the Sun. The star is drifting closer with a radial velocity of −5 km/s.[6]

This is an orange-hued[11] K-type giant star with a stellar classification of K1 II/III.[4] At the age of 1.5[7] billion years old, it has exhausted the supply of hydrogen at its core then cooled and expanded off the main sequence. Epsilon Columbae has 2.5[7] times the mass and 25[8] times the radius of the Sun. The star radiates 251 times the solar luminosity from its enlarged photosphere at an effective temperature of 4,575 K.[8] It has a peculiar velocity of 30.0±3.9 km/s, making it a candidate runaway star system.[12] Based upon changes in the star's movement, it has an orbiting stellar companion of unknown type.[13]

References

  1. ↑ 1.0 1.1 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A.  XHIP record for this object at VizieR.
  2. ↑ 2.0 2.1 2.2 2.3 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.
  3. ↑ 3.0 3.1 3.2 3.3 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. 
  4. ↑ 4.0 4.1 Houk, Nancy (1982), Michigan catalogue of two-dimensional spectral types for the HD stars, 3, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode: 1982mcts.book.....H. 
  5. ↑ Luck, R. Earle (2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal 150 (3): 88, doi:10.1088/0004-6256/150/3/88, Bibcode: 2015AJ....150...88L. 
  6. ↑ 6.0 6.1 Gontcharov, G. A. (2006), "Pulkovo compilation of radial velocities for 35495 stars in a common system", Astronomy Letters 32 (11): 759–771, doi:10.1134/S1063773706110065, Bibcode: 2006AstL...32..759G. 
  7. ↑ 7.0 7.1 7.2 7.3 Luck, R. Earle (September 2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal 150 (3): 23, doi:10.1088/0004-6256/150/3/88, 88, Bibcode: 2015AJ....150...88L. 
  8. ↑ 8.0 8.1 8.2 8.3 8.4 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. Bibcode: 2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  9. ↑ 9.0 9.1 9.2 Soubiran, C. et al. (July 1, 2022), "Assessment of [Fe/H] determinations for FGK stars in spectroscopic surveys", Astronomy and Astrophysics 663: A4, doi:10.1051/0004-6361/202142409, ISSN 0004-6361, Bibcode: 2022A&A...663A...4S. 
  10. ↑ "eps Col". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=eps+Col. 
  11. ↑ Kambic, Bojan (2009), Viewing the Constellations with Binoculars: 250+ Wonderful Sky Objects to See and Explore, The Patrick Moore Practical Astronomy Series, Springer Science & Business Media, p. 260, ISBN 978-0387853550, https://books.google.com/books?id=3vxLNPNHOcwC&pg=PA260. 
  12. ↑ Tetzlaff, N. et al. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society 410 (1): 190–200, doi:10.1111/j.1365-2966.2010.17434.x, Bibcode: 2011MNRAS.410..190T. 
  13. ↑ 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, Bibcode: 2008MNRAS.389..869E.