Zeta Scuti

ζ Scuti
Location of ζ Scuti (circled)
Observation data
Epoch J2000      Equinox J2000
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 mas[1]
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
ζ Sct, BD−09° 4712, GC 25101, HD 169156, HIP 90135, HR 6884, SAO 142267, GSC 05690-01263
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. ^ a b c d e van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
  2. ^ a b c d e f Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644. Vizier catalog entry
  3. ^ a b c 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, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  4. ^ a b Mallama, A. (2014). "Sloan Magnitudes for the Brightest Stars". The Journal of the American Association of Variable Star Observers. 42 (2): 443. Bibcode:2014JAVSO..42..443M.Vizier catalog entry
  5. ^ a b Pourbaix, D.; Tokovinin, A. A.; Batten, A. H.; Fekel, F. C.; Hartkopf, W. I.; Levato, H.; Morrell, N. I.; Torres, G.; Udry, S. (2004). "SB9: The ninth catalogue of spectroscopic binary orbits". Astronomy and Astrophysics. 424 (2): 727–732. arXiv:astro-ph/0406573. Bibcode:2004A&A...424..727P. doi:10.1051/0004-6361:20041213. S2CID 119387088.
  6. ^ Jancart, S. (2005). "Astrometric orbits of SB9 stars". Astronomy and Astrophysics. 442 (1): 365–380. arXiv:astro-ph/0507695. Bibcode:2005A&A...442..365J. doi:10.1051/0004-6361:20053003. S2CID 15123997.
  7. ^ a b c d 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. arXiv:astro-ph/9911002. Bibcode:1999A&A...352..555A. Vizier catalog entry
  8. ^ a b Gontcharov, G. A. (2009). "Red giant clump in the Tycho-2 catalogue". Astronomy Letters. 34 (11): 785–796. arXiv:1607.00619. Bibcode:2008AstL...34..785G. doi:10.1134/S1063773708110078. S2CID 73524157. 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. arXiv:1312.3474. Bibcode:2014A&A...561A.126D. doi:10.1051/0004-6361/201220762. S2CID 54046583. Vizier catalog entry