Astronomy:Zeta Scuti

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Short description: Star in the constellation Scutum
ζ Scuti
Scutum constellation map.svg
Red circle.svg
Location of ζ Scuti (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Scutum
Right ascension  18h 23m 39.58309s[1]
Declination −8° 56′ 03.7885″[1]
Apparent magnitude (V) 4.66[2]
Characteristics
Spectral type G9 IIIb Fe-0.5[3]
U−B color index +0.72[4]
B−V color index +0.94[4]
Astrometry
Radial velocity (Rv)−5.02[5] km/s
Proper motion (μ) RA: +49.59[1] mas/yr
Dec.: +51.24[1] mas/yr
Parallax (π)15.78 ± 1.02[1] mas
Distance210 ± 10 ly
(63 ± 4 pc)
Absolute magnitude (MV)0.66[2]
Orbit[6]
Primaryζ Scuti A
Companionζ Scuti B
Period (P)2373.7 days
Semi-major axis (a)21.6 mas
Eccentricity (e)0.1
Inclination (i)89°
Longitude of the node (Ω)226°
Periastron epoch (T)2418278.3
Argument of periastron (ω)
(secondary)
242.1°
Details
Mass1.29[7] M
Radius9.3[7] R
Luminosity62.04[2] L
Surface gravity (log g)2.61[7] cgs
Temperature4,750[8] K
Metallicity [Fe/H]−0.08[2] dex
Rotational velocity (v sin i)1.5[9] km/s
Other designations
Database references
SIMBADdata

Zeta Scuti, Latinized from ζ Scuti, is the Bayer designation for a star in the southern constellation of Scutum. It is a faint star but visible to the naked eye with an apparent magnitude of 4.66.[2] The distance to this star, as determined via parallax measurement, is around 210 light years. It is moving closer to the Sun with a radial velocity of −5 km/s.[5]

This is an astrometric binary system with a period of 6.5 years (2,374 days) and an orbital eccentricity of 0.10.[3] The visible component is an aging giant star of type G with a stellar classification of G9 IIIb Fe−0.5.[3] The suffix notation indicates the spectrum displays a mild underabundance of iron. It has 1.29 times the mass of the Sun and has expanded to 9.3 times the Sun's radius.[7] The star is radiating 62[2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,750 K.[8]

References

  1. 1.0 1.1 1.2 1.3 1.4 van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode2007A&A...474..653V. 
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode2012AstL...38..331A.  Vizier catalog entry
  3. 3.0 3.1 3.2 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. 
  4. 4.0 4.1 Mallama, A. (2014). "Sloan Magnitudes for the Brightest Stars". The Journal of the American Association of Variable Star Observers 42 (2): 443. Bibcode2014JAVSO..42..443M. Vizier catalog entry
  5. 5.0 5.1 Pourbaix, D.; Tokovinin, A. A.; Batten, A. H.; Fekel, F. C.; Hartkopf, W. I.; Levato, H.; Morrell, N. I.; Torres, G. et al. (2004). "SB9: The ninth catalogue of spectroscopic binary orbits". Astronomy and Astrophysics 424 (2): 727–732. doi:10.1051/0004-6361:20041213. Bibcode2004A&A...424..727P. 
  6. Jancart, S. (2005). "Astrometric orbits of SB9 stars". Astronomy and Astrophysics 442 (1): 365–380. doi:10.1051/0004-6361:20053003. Bibcode2005A&A...442..365J. 
  7. 7.0 7.1 7.2 7.3 Allende Prieto, C.; Lambert, D. L. (1999). "Fundamental parameters of nearby stars from the comparison with evolutionary calculations: Masses, radii and effective temperatures". Astronomy and Astrophysics 352: 555–562. Bibcode1999A&A...352..555A.  Vizier catalog entry
  8. 8.0 8.1 Gontcharov, G. A. (2009). "Red giant clump in the Tycho-2 catalogue". Astronomy Letters 34 (11): 785–796. doi:10.1134/S1063773708110078. Bibcode2008AstL...34..785G.  Vizier catalog entry
  9. De Medeiros, J. R.; Alves, S.; Udry, S.; Andersen, J.; Nordström, B.; Mayor, M. (2014). "A catalog of rotational and radial velocities for evolved stars". Astronomy & Astrophysics 561: A126. doi:10.1051/0004-6361/201220762. Bibcode2014A&A...561A.126D.  Vizier catalog entry