V424 Lacertae

From Wikipedia, the free encyclopedia
V424 Lacertae
Lacerta constellation map.svg
Red circle.svg
Location of V424 Lacertae (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Lacerta
Right ascension 22h 56m 25.997s[1]
Declination +49° 44′ 00.716″[1]
Apparent magnitude (V) +4.94[2]
Characteristics
Spectral type K5 Ib[3]
U−B color index +1.95[2]
B−V color index +1.77[2]
Variable type Lc[4]
Astrometry
Radial velocity (Rv)−9.50[5] km/s
Proper motion (μ) RA: −0.709 ± 0.298[6] mas/yr
Dec.: −2.317 ± 0.294[6] mas/yr
Parallax (π)1.5762 ± 0.1858[6] mas
Distanceapprox. 2,100 ly
(approx. 630 pc)
Absolute magnitude (MV)−4.27[7]
Details
Mass6.8[8] M
Radius274+4
−3
[9] R
Luminosity13,100 - 14,200[1] L
Surface gravity (log g)+0.50[8] cgs
Temperature3,790[1] K
Other designations
V424 Lac, BD+48° 3887, HR 8726, HD 216946, BD+48°3887, HIP 113288, SAO 52516
Database references
SIMBADdata

V424 Lacertae (V424 Lac) is a red supergiant variable star in the constellation Lacerta. It is a member of the Lacerta OB1 stellar association.

The MK spectral type of V424 Lac has been determined to be K5,[3] but it has also been classified as M0.[7] It was discovered to be slightly variable using analysis of Hipparcos photometry. The total range is less than a tenth of a magnitude.[10] Multiple short periods are detected, as well as slow variations with a period of 1,100 or 1,601 days. Although listed in the General Catalogue of Variable Stars as a slow irregular variable, it has been considered to be either a semiregular variable or long secondary period variable.[11]

There is an ultraviolet excess from V424 Lacertae, that may be due to an unseen companion, which could also explain the long secondary period. On this assumption, a sub-stellar companion in a 1,382 day 6.2 AU orbit has been suggested.[8]

References[]

  1. ^ a b c d Messineo, M.; Brown, A. G. A. (2019). "A Catalog of Known Galactic K-M Stars of Class I Candidate Red Supergiants in Gaia DR2". The Astronomical Journal. 158 (1): 20. arXiv:1905.03744. Bibcode:2019AJ....158...20M. doi:10.3847/1538-3881/ab1cbd. S2CID 148571616.
  2. ^ a b c 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: 0. Bibcode:2002yCat.2237....0D.
  3. ^ a b Keenan, Philip C.; McNeil, Raymond C. (1989). "The Perkins catalog of revised MK types for the cooler stars". Astrophysical Journal Supplement Series. 71: 245. Bibcode:1989ApJS...71..245K. doi:10.1086/191373.
  4. ^ Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
  5. ^ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
  6. ^ a b c 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.
  7. ^ a b Levesque, Emily M.; Massey, Philip; Olsen, K. A. G.; Plez, Bertrand; Josselin, Eric; Maeder, Andre; Meynet, Georges (2005). "The Effective Temperature Scale of Galactic Red Supergiants: Cool, but Not As Cool As We Thought". The Astrophysical Journal. 628 (2): 973–985. arXiv:astro-ph/0504337. Bibcode:2005ApJ...628..973L. doi:10.1086/430901. S2CID 15109583.
  8. ^ a b c Lee, B.-C.; Han, I.; Park, M.-G.; Hatzes, A. P.; Kim, K.-M. (2014). "Low-amplitude and long-period radial velocity variations in giants HD 3574, 63 Cygni, and HD 216946". Astronomy & Astrophysics. 566: A124. arXiv:1405.5955. Bibcode:2014A&A...566A.124L. doi:10.1051/0004-6361/201321863. S2CID 54177778.
  9. ^ Norris, Ryan P. (2019). Seeing Stars Like Never Before: A Long-term Interferometric Imaging Survey of Red Supergiants (PDF) (PhD). Georgia State University.
  10. ^ Kazarovets, E. V.; Samus, N. N.; Durlevich, O. V.; Frolov, M. S.; Antipin, S. V.; Kireeva, N. N.; Pastukhova, E. N. (1999). "The 74th Special Name-list of Variable Stars". Information Bulletin on Variable Stars. 4659: 1. Bibcode:1999IBVS.4659....1K.
  11. ^ Messina, Sergio (2007). "Evidence for the pulsational origin of the Long Secondary Periods: The red supergiant star V424 Lac (HD 216946)". New Astronomy. 12 (7): 556–561. Bibcode:2007NewA...12..556M. doi:10.1016/j.newast.2007.04.002.
Retrieved from ""