19 Lyrae

In this article, the topic of 19 Lyrae will be addressed, which has become very relevant today. 19 Lyrae has captured the attention of people around the world due to its impact on various aspects of daily life. Since its emergence, 19 Lyrae has generated extensive debate and has given rise to many conflicting opinions. Throughout this text, different perspectives on 19 Lyrae will be analyzed, as well as its implications in today's society. Possible solutions or alternatives to address this phenomenon will also be explored, in order to provide a comprehensive and enriching vision of 19 Lyrae.

19 Lyrae

A light curve for 19 Lyrae, plotted from TESS data[1]
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Lyra
Right ascension 19h 11m 46.008s[2]
Declination +31° 17′ 00.44″[2]
Apparent magnitude (V) 5.93[3]
Characteristics
Spectral type B8 IIIp Si Sr[4]
B−V color index −0.062±0.004[3]
Variable type α2 CVn[5]
Astrometry
Radial velocity (Rv)−30.1±2.9[3] km/s
Proper motion (μ) RA: −4.143 mas/yr[2]
Dec.: −2.763 mas/yr[2]
Parallax (π)3.4213±0.0417 mas[2]
Distance950 ± 10 ly
(292 ± 4 pc)
Absolute magnitude (MV)−1.24[3]
Details
Mass3.76±0.22[6] M☉
Radius6.40[7] R☉
Luminosity397.48[3] L☉
Temperature11,194+501
−479[6] K
Rotational velocity (v sin i)35[8] km/s
Other designations
19 Lyr, V471 Lyr, NSV 11806, BD+31°3497, FK5 3532, GC 26459, HD 179527, HIP 94311, HR 7283, SAO 67946[9]
Database references
SIMBADdata

19 Lyrae is a single[10] variable star located approximately 950[2] light years away from the Sun in the northern constellation of Lyra.[9] It has the variable star designation V471 Lyr, while 19 Lyrae is the Flamsteed designation. This object is just bright enough to be visible to the naked eye, appearing as a dim, blue-white star with a baseline apparent visual magnitude of 5.93.[3] It is moving closer to the Earth with a heliocentric radial velocity of −30 km/s, and may come as close as 167 light-years around 8.5 million years from now.[3]

This is a magnetic chemically-peculiar star[11] with a stellar classification of B8 IIIp Si Sr,[4] showing abundance anomalies in silicon and strontium. The light variations of this star were discovered by J. E. Winzer in 1974.[12] It is an Alpha2 Canum Venaticorum-type variable with a period of 1.160898 days (or 7.0980 days[12]), ranging in magnitude from a high of 5.91 down to 5.98.[5] The surface magnetic field has a strength of (111.3±56.9)×10−4 T[13]

19 Lyrae has a moderate rotation rate, showing a projected rotational velocity of 35 km/s.[8] Stellar models give it an estimated 3.8[6] times the mass of the Sun and its girth is measured at 6.4[7] times the Sun's radius. It is radiating 397[3] times the luminosity of the Sun from its photosphere at an effective temperature of around 11,194 K.[6] The star has an absolute magnitude of −1.24,[3] which shows how bright the star would appear if it were located at a distance of 10 parsecs (33 ly) from the Sun.

References

  1. ^ MAST: Barbara A. Mikulski Archive for Space Telescopes, Space Telescope Science Institute, retrieved 8 December 2021.
  2. ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  3. ^ a b c d e f g h i 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.
  4. ^ a b Abt, Helmut A.; Morrell, Nidia I. (1995), "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars", Astrophysical Journal Supplement, 99: 135, Bibcode:1995ApJS...99..135A, doi:10.1086/192182
  5. ^ a b Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/s1063772917010085, S2CID 125853869.
  6. ^ a b c d Netopil, Martin; et al. (July 2017), "An Investigation of the Rotational Properties of Magnetic Chemically Peculiar Stars", Monthly Notices of the Royal Astronomical Society, 468 (3): 2745–2756, arXiv:1703.05218, Bibcode:2017MNRAS.468.2745N, doi:10.1093/mnras/stx674.
  7. ^ a b Shulyak, D.; et al. (2014), "Interferometry of chemically peculiar stars: Theoretical predictions versus modern observing facilities", Monthly Notices of the Royal Astronomical Society, 443 (2): 1629, arXiv:1406.6093, Bibcode:2014MNRAS.443.1629S, doi:10.1093/mnras/stu1259.
  8. ^ a b Abt, Helmut A.; et al. (July 2002), "Rotational Velocities of B Stars", The Astrophysical Journal, 573 (1): 359–365, Bibcode:2002ApJ...573..359A, doi:10.1086/340590
  9. ^ a b "19 Lyr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-05-30.
  10. ^ 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, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  11. ^ Kochukhov, O.; Bagnulo, S. (2006), "Evolutionary state of magnetic chemically peculiar stars", Astronomy and Astrophysics, 450 (2): 763, arXiv:astro-ph/0601461, Bibcode:2006A&A...450..763K, doi:10.1051/0004-6361:20054596, S2CID 18596834
  12. ^ a b Adelman, S. J.; Rice, R. H. (April 1999), "UVBY photometry of the mCP stars HD 35298, 19 Lyrae, HD 192678, and HR 8216", Astronomy and Astrophysics Supplement, 136: 111–115, Bibcode:1999A&AS..136..111A, doi:10.1051/aas:1999202.
  13. ^ Bychkov, V. D.; et al. (2009), "Catalogue of averaged stellar effective magnetic fields - II. Re-discussion of chemically peculiar A and B stars", Monthly Notices of the Royal Astronomical Society, 394 (3): 1338, Bibcode:2009MNRAS.394.1338B, doi:10.1111/j.1365-2966.2008.14227.x, S2CID 120268049.