Delta1 Lyrae

In this article we will address the topic of Delta1 Lyrae, which has been the subject of interest and debate in various areas. Delta1 Lyrae has captured the attention of experts and the general public due to its relevance and impact in today's society. Throughout history, Delta1 Lyrae has played a fundamental role in different aspects, whether in the social, cultural, technological, political, economic, among others. In this article, we will explore the various dimensions and perspectives related to Delta1 Lyrae, with the aim of providing a comprehensive and enriching vision on this topic.

For other stars with this Bayer designation, see δ Lyrae.
Delta1 Lyrae
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Lyra
Right ascension 18h 53m 43.55924s[1]
Declination +36° 58′ 18.1891″[1]
Apparent magnitude (V) 5.56[2]
Characteristics
Spectral type B2.5V[3][4]
U−B color index −0.67[2]
B−V color index −0.15[2]
Astrometry
Radial velocity (Rv)−25.8[5] km/s
Proper motion (μ) RA: +1.350[1] mas/yr
Dec.: −2.985[1] mas/yr
Parallax (π)2.8072±0.1334 mas[1]
Distance1,160 ± 60 ly
(360 ± 20 pc)
Absolute magnitude (MV)−1.55[6]
Orbit[7]
Period (P)88.352 days
Semi-major axis (a)≥46.8 Gm (0.313 AU)
Eccentricity (e)0.37±0.03
Periastron epoch (T)2428406.613±0.500 JD
Argument of periastron (ω)
(secondary)		191.3±0.1°
Semi-amplitude (K1)
(primary)		39.7±1.8 km/s
Details
δ1 Lyr A
Mass7.9±0.1 M☉[4]
7.75±0.50 M☉[8]
6.6+0.68
−0.61[9] M☉
Luminosity838[6] L☉
Luminosity (bolometric)3,620[8] L☉
Surface gravity (log g)3.764±0.032 (3.848 polar)[10] cgs
Temperature20,350[8] K
Metallicity −0.05[6] dex
Rotational velocity (v sin i)86±10[10] km/s
Age21.1±2.2 Myr[4]
9+9
−4[9] Myr
Other designations
Delta1 Lyr, 11 Lyrae, NSV 11504, BD+36°3307, GC 25934, HD 175426, HIP 92728, HR 7131, SAO 67537, WDS J18537+3658A, GSC 02650-02146[11]
Database references
SIMBADdata

Delta1 Lyrae, its name Latinized from δ1 Lyrae, is a binary star system in the northern constellation of Lyra. It is dimly visible to the naked eye at night with a combined apparent visual magnitude of 5.56.[2] The system is located at a distance of approximately 1,160 light years from the Sun based on parallax,[1] but is drifting closer with a radial velocity of −26 km/s.[5] O. J. Eggen originally included this as a candidate member of the proposed Delta Lyrae cluster.[12]

The variable radial velocity of this star was discovered from photographic plates taken at the Yerkes Observatory in 1904.[13] The first set of orbital elements was computed by Frank Craig Jordan in 1916.[14] It is a single-lined spectroscopic binary with an orbital period of 88.4 days and an eccentricity (ovalness) of 0.37.[7]

The visible component of the pair has a blue-white hue with a stellar classification of B2.5V,[3][4] indicating that it is a B-type main-sequence star undergoing core hydrogen fusion. It is a few million years old with a relatively high rotation rate and around 7–8 times the mass of the Sun. The star is radiating about 3,620[8] times the Sun's luminosity from its photosphere at an effective temperature of 20,350 K.[8]

There is a magnitude 9.93 visual companion at an angular separation of 175.30 arcseconds along a position angle of 20°, as of 2012. This component was discovered by William Herschel.[15] It is an evolved giant star with a class of K2III at a distance of around 1,760 light years.[16]

References

  1. ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. ^ a b c d Guetter, H. H. (October 1974), "UBV photometry of 180 early-type stars", Publications of the Astronomical Society of the Pacific, 86: 795–797, Bibcode:1974PASP...86..795G, doi:10.1086/129675.
  3. ^ a b Guetter, Harry H. (April 1968), "Spectral classification of 239 early-type stars", Publications of the Astronomical Society of the Pacific, 80 (473): 197, Bibcode:1968PASP...80..197G, doi:10.1086/128611, S2CID 121565803.
  4. ^ a b c d 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, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x, S2CID 118629873.
  5. ^ a b Wilson, Ralph Elmer (1953), "General catalogue of stellar radial velocities", Carnegie Institute Washington D.C. Publication, Carnegie Institution of Washington, Bibcode:1953GCRV..C......0W.
  6. ^ a b c 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.
  7. ^ a b Richardson, E. H.; McKellar, A. (1957), "Redetermination of the spectrographic orbit of delta1 Lyrae", Publ. Dominion Astrophys. Obs., 10: 407–413, Bibcode:1958PDAO...10..407R. , p. 412
  8. ^ a b c d e Hohle, M. M.; et al. (April 2010), "Masses and luminosities of O- and B-type stars and red supergiants", Astronomische Nachrichten, 331 (4): 349, arXiv:1003.2335, Bibcode:2010AN....331..349H, doi:10.1002/asna.200911355, S2CID 111387483.
  9. ^ a b Gullikson, Kevin; et al. (July 26, 2016), "The Close Companion Mass-ratio Distribution of Intermediate-mass Stars", The Astronomical Journal, 152 (2): 40–53, arXiv:1604.06456, Bibcode:2016AJ....152...40G, doi:10.3847/0004-6256/152/2/40, S2CID 119179065.
  10. ^ a b Huang, W.; Gies, D. R. (August 2008), "Stellar Rotation in Field and Cluster B Stars", The Astrophysical Journal, 683 (2): 1045–1051, arXiv:0805.2133, Bibcode:2008ApJ...683.1045H, doi:10.1086/590106, S2CID 18926523.
  11. ^ "del01 Lyr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-01-23.{{cite web}}: CS1 maint: postscript (link)
  12. ^ Eggen, O. J. (July 1983), "Concentrations in the Local Association- II. The northern concentrations including the alf Per, Pleiades, M 34 and del LYR clusters.", Monthly Notices of the Royal Astronomical Society, 204: 391–403, Bibcode:1983MNRAS.204..391E, doi:10.1093/mnras/204.2.391.
  13. ^ Frost, E. B.; Adams, W. S. (1904), "Observations with the Bruce spectrograph", The Astrophysical Journal, 19: 352, Bibcode:1904ApJ....19..350F, doi:10.1086/141124.
  14. ^ Jordan, Frank Craig (1916), "The orbit of 1 Lyrae", Publications of the Allegheny Observatory of the University of Pittsburgh, 3 (14): 119–124, Bibcode:1916PAllO...3..119J.
  15. ^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122 (6): 3466–3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920.
  16. ^ "BD+36 3308". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-01-23.{{cite web}}: CS1 maint: postscript (link)