R Lyrae

Last updated
R Lyrae
Lyra constellation map.svg
R Lyrae (labelled as 13)
Observation data
Epoch J2000.0       Equinox J2000.0
Constellation Lyra
Right ascension 18h 55m 20.101223s [1]
Declination +43° 56 45.9215 [1]
Apparent magnitude  (V)4.00 [2] (3.9 - 5.0 [3] )
Characteristics
Spectral type M5 III [4]
Apparent magnitude  (J)0.90 [2]
U−B color index +1.41 [2]
B−V color index +1.59 [2]
Variable type SRb [3]
Astrometry
Radial velocity (Rv)27.15 [5]  km/s
Proper motion (μ)RA: 21.05 [1]   mas/yr
Dec.: 82.06 [1]   mas/yr
Parallax (π)10.94 ± 0.12  mas [1]
Distance 298 ± 3  ly
(91 ± 1  pc)
Absolute magnitude  (MV)1.1 [4]
Details
Mass 1.80 [6]   M
Luminosity 4,168 [6]   L
Surface gravity (log g)0.47 [7]   cgs
Temperature 3,313 [6]   K
Other designations
R  Lyrae, 13  Lyrae, HR  7157, BD+43°3117, HD  175865, SAO  47919, HIP  92862, GC  25996, GSC  03131-02155
Database references
SIMBAD data
R Lyrae near Vega RLyr.jpg
R Lyrae near Vega

R Lyrae, also known as its Flamsteed designation 13 Lyrae, is a 4th magnitude semiregular variable star in the constellation Lyra, approximately 350 light years away from Earth. It is a red giant star of the spectral type M5III, meaning it has a surface temperature of under 3,500 kelvins. It is much larger and brighter, yet cooler, than the Sun. In the near-infrared J band, it is brighter than the nearby Vega.

R Lyrae is unusual in that it is a red star with a high proper motion, greater than 50 milliarcseconds a year. [8]

Visual band light curves for R Lyrae, adapted from Percy et al. (2001) RLyrLightCurve.png
Visual band light curves for R Lyrae, adapted from Percy et al. (2001)

The variability is not consistent and regular, but periods of 46, 64, 378, and 1,000 days have been reported, with the 46-day period being the strongest. [4] [10]

It is calculated that R Lyrae was a 2.0 M star on the main sequence. It is considered an oxygen-rich asymptotic giant branch star, with both hydrogen and helium shells fusing. [6]

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References

  1. 1 2 3 4 5 van Leeuwen, Floor (13 August 2007). "Validation of the new Hipparcos reduction". Astronomy & Astrophysics. 474 (2): 653–664. arXiv: 0708.1752 . Bibcode:2007A&A...474..653V. doi: 10.1051/0004-6361:20078357 . eISSN   1432-0746. ISSN   0004-6361.
  2. 1 2 3 4 Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237. Bibcode:2002yCat.2237....0D.
  3. 1 2 "GCVS Query=R Lyr". General Catalogue of Variable Stars @ Sternberg Astronomical Institute, Moscow, Russia . Retrieved 2012-08-22.
  4. 1 2 3 Yeşilyaprak, C.; Aslan, Z. (2004). "Period-luminosity relation for M-type semiregular variables from Hipparcos parallaxes". Monthly Notices of the Royal Astronomical Society. 355 (2): 601. Bibcode:2004MNRAS.355..601Y. doi: 10.1111/j.1365-2966.2004.08344.x .
  5. Famaey, B.; Pourbaix, D.; Frankowski, A.; Van Eck, S.; Mayor, M.; Udry, S.; Jorissen, A. (2009). "Spectroscopic binaries among Hipparcos M giants,. I. Data, orbits, and intrinsic variations". Astronomy and Astrophysics. 498 (2): 627. arXiv: 0901.0934 . Bibcode:2009A&A...498..627F. doi:10.1051/0004-6361/200810698. S2CID   18739721.
  6. 1 2 3 4 Halabi, Ghina M.; Eid, Mounib El (2015). "Exploring masses and CNO surface abundances of red giant stars". Monthly Notices of the Royal Astronomical Society. 451 (3): 2957. arXiv: 1507.01517 . Bibcode:2015MNRAS.451.2957H. doi:10.1093/mnras/stv1141. S2CID   118707332.
  7. Prugniel, Ph.; Vauglin, I.; Koleva, M. (2011). "The atmospheric parameters and spectral interpolator for the MILES stars". Astronomy & Astrophysics. 531: A165. arXiv: 1104.4952 . Bibcode:2011A&A...531A.165P. doi:10.1051/0004-6361/201116769. S2CID   54940439.
  8. Jiménez-Esteban, F. M.; Caballero, J. A.; Dorda, R.; Miles-Páez, P. A.; Solano, E. (2012). "Identification of red high proper-motion objects in Tycho-2 and 2MASS catalogues using Virtual Observatory tools". Astronomy & Astrophysics. 539: 12. arXiv: 1201.5315 . Bibcode:2012A&A...539A..86J. doi:10.1051/0004-6361/201118375. S2CID   53404166.
  9. Percy, John R.; Wilson, Joseph B.; Henry, Gregory W. (August 2001). "Long-Term VRI Photometry of Small-Amplitude Red Variables. I. Light Curves and Periods". Publications of the Astronomical Society of the Pacific. 113 (786): 983–996. Bibcode:2001PASP..113..983P. doi: 10.1086/322153 . S2CID   14609175.
  10. Glass, I. S.; Van Leeuwen, F. (2007). "Semiregular variables in the solar neighbourhood". Monthly Notices of the Royal Astronomical Society. 378 (4): 1543–1549. arXiv: 0704.3150 . Bibcode:2007MNRAS.378.1543G. doi:10.1111/j.1365-2966.2007.11903.x. S2CID   14332208.