Astronomy:20 Canum Venaticorum

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Short description: Star in the constellation Canes Venatici
20 Canum Venaticorum
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A light curve for AO Canum Venaticorum, plotted from TESS data[1]
Observation data
Equinox J2000.0]] (ICRS)
Constellation Canes Venatici
Right ascension  13h 17m 32.54093s[2]
Declination +40° 34′ 21.3875″[2]
Apparent magnitude (V) +4.70 - 4.75[3]
Characteristics
Spectral type A9 II mF2[4]
B−V color index 0.30[5]
Variable type δ Sct[6]
Astrometry
Radial velocity (Rv)9.32±0.16[7] km/s
Proper motion (μ) RA: −113.761[2] mas/yr
Dec.: +19.858[2] mas/yr
Parallax (π)13.7210 ± 0.1581[2] mas
Distance238 ± 3 ly
(72.9 ± 0.8 pc)
Details
Mass2.43[5] M
Radius5.1[8] R
Luminosity63[5] L
Surface gravity (log g)2.97[9] cgs
Temperature7,314±42[5] K
Metallicity [Fe/H]0.18[10] dex
Rotational velocity (v sin i)15[11] km/s
Age750[5] Myr
Other designations
20 CVn, AO Canum Venaticorum, BD+41°2380, FK5 494, GC 18000, HD 115604, HIP 64844, HR 5017, SAO 44549[12]
Database references
SIMBADdata

20 Canum Venaticorum is a single[13] variable star in the northern constellation of Canes Venatici, located 238 light years from the Sun. This object has the variable star designation AO Canum Venaticorum; 20 Canum Venaticorum is the Flamsteed designation. It is visible to the naked eye as a faint, white-hued star with an apparent visual magnitude around +4.7. The star is moving further from the Earth with a heliocentric radial velocity of +9 km/s.[7] Eggen (1971) listed this star as a member of the Hyades Stream.[14]

This star has a stellar classification of A9 II mF2, which indicates the hydrogen line matches an A-type bright giant but the metal lines are closer to an F-type star. However, it does not appear to be an Am star as the Calcium K line is normal.[4] Earlier, Morgan and Abt (1972) assigned it a giant star class of F3 III.[15] It has also been listed as a spectral standard for class F3 III.[16]

William Henry Wehlau et al. announced that the star's brightness varies, in 1966.[17] It is classified as a Delta Scuti variable with a single radial pulsation mode providing the best fit to the observed variation.[6] Its brightness varies from magnitude +4.70 to +4.75 with a period of 2.92 hours.[3]

20 Canum Venaticorum is 750 million years old with 2.43 times the mass of the Sun and five times the Sun's radius. It is radiating 63 times the Sun's luminosity from its photosphere at an effective temperature of 7,314 K.[5]

References

  1. MAST: Barbara A. Mikulski Archive for Space Telescopes, Space Telescope Science Institute, https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html, retrieved 8 December 2021. 
  2. 2.0 2.1 2.2 2.3 2.4 van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode2007A&A...474..653V. 
  3. 3.0 3.1 Samus, N. N. et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1 61 (1): 80–88, doi:10.1134/s1063772917010085, Bibcode2017ARep...61...80S. 
  4. 4.0 4.1 Gray, R. O. et al. (2001), "The Physical Basis of Luminosity Classification in the Late A-, F-, and Early G-Type Stars. I. Precise Spectral Types for 372 Stars", The Astronomical Journal 121 (4): 2148, doi:10.1086/319956, Bibcode2001AJ....121.2148G. 
  5. 5.0 5.1 5.2 5.3 5.4 5.5 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. 
  6. 6.0 6.1 Chadid, M. et al. (August 2001), "20 CVn: A monoperiodic radially pulsating delta Scuti star", Astronomy and Astrophysics 375: 113–121, doi:10.1051/0004-6361:20010809, Bibcode2001A&A...375..113C. 
  7. 7.0 7.1 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.
  8. Fetherolf, Tara; Pepper, Joshua; Simpson, Emilie; Kane, Stephen R.; Močnik, Teo; English, John Edward; Antoci, Victoria; Huber, Daniel et al. (2023). "Variability Catalog of Stars Observed during the TESS Prime Mission". The Astrophysical Journal Supplement Series 268 (1): 4. doi:10.3847/1538-4365/acdee5. Bibcode2023ApJS..268....4F. 
  9. Adamczak, Jens; Lambert, David L. (August 2014), "Carbon and Oxygen Abundances across the Hertzsprung Gap", The Astrophysical Journal 791 (1): 12, doi:10.1088/0004-637X/791/1/58, 58, Bibcode2014ApJ...791...58A. 
  10. Massarotti, Alessandro et al. (January 2008), "Rotational and Radial Velocities for a Sample of 761 HIPPARCOS Giants and the Role of Binarity", The Astronomical Journal 135 (1): 209–231, doi:10.1088/0004-6256/135/1/209, Bibcode2008AJ....135..209M. 
  11. Royer, F. et al. (October 2002), "Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i", Astronomy and Astrophysics 393: 897–911, doi:10.1051/0004-6361:20020943, Bibcode2002A&A...393..897R. 
  12. "20 CVn". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=20+CVn. 
  13. Eggleton, P. P.; Tokovinin, A. A. (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. 
  14. Eggen, O. J. (December 1971), "Luminosities and Motions of the F-Type Stars. I. Luminosity and Metal Abundance Indices for Disk Population Stars", Publications of the Astronomical Society of the Pacific 83 (496): 741, doi:10.1086/129211, Bibcode1971PASP...83..741E. 
  15. Morgan, W. W.; Abt, H. A. (February 1972), "The spectral classification of the F stars of intermediate luminosity", Astronomical Journal 77: 35–37, doi:10.1086/111242, Bibcode1972AJ.....77...35M. 
  16. Morgan, W. W.; Abt, Helmut A.; Tapscott, J. W. (1978), Revised MK Spectral Atlas for stars earlier than the sun, Bibcode1978rmsa.book.....M 
  17. Wehlau, W. H.; Chen, S. C. N.; Symonds, G. (July 1966), "Light Variability of 20 Canum Venaticorum", Information Bulletin on Variable Stars 143: 1-2, Bibcode1966IBVS..143....1W.