Jump to content

Beta Lacertae

From Wikipedia, the free encyclopedia
(Redirected from HR 8538)
β Lacertae

β Lacertae in optical light
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Lacerta
Right ascension 22h 23m 33.624s[1]
Declination +52° 13′ 44.56″[1]
Apparent magnitude (V) 4.43[2]
Characteristics
Spectral type G8 III[3]
U−B color index +0.77[4]
B−V color index +1.02[4]
V−R color index 0.6[2]
R−I color index +0.57[4]
Astrometry
Radial velocity (Rv)−10.4 ± 0.9[2] km/s
Proper motion (μ) RA: −13.25±0.13[1] mas/yr
Dec.: −186.77±0.13[1] mas/yr
Parallax (π)19.19 ± 0.16 mas[1]
Distance170 ± 1 ly
(52.1 ± 0.4 pc)
Absolute magnitude (MV)+0.67[5]
Details[5]
Mass0.97±0.21[3] M
Radius10.96±0.23[3] R
Luminosity57.7±3.0[3] L
Surface gravity (log g)2.43 cgs
Temperature4803±75[3] K
Metallicity [Fe/H]−0.33 dex
Rotational velocity (v sin i)< 17[4] km/s
Age6.76±3.59[3] Gyr
Other designations
β Lac, Beta Lacertae, Beta Lac, 3 Lacertae, 3 Lac, BD+51 3358, FK5 844, GC 31310, HD 212496, HIP 110538, HR 8538, NLTT 53741, PPM 40598, SAO 34395[2]
Database references
SIMBADdata

Beta Lacertae (Beta Lac, β Lacertae, β Lac) is the fourth-brightest star in the constellation of Lacerta. Based upon an annual parallax shift of 19.19 mas,[1] it is 170 light-years distant from Earth. At that distance, the visual magnitude is diminished by an extinction factor of 0.17 due to interstellar dust.[5]

This is an evolved G-type giant with an apparent visual magnitude of approximately 4.43.[2] It is a red clump[6] star and the primary component of a suspected binary system, with the pair having an angular separation of 0.2 arcsecond.[7]

Naming

[edit]

In Chinese, 螣蛇 (Téng Shé), meaning Flying Serpent, refers to an asterism consisting of β Lacertae, α Lacertae, 4 Lacertae, π2 Cygni, π1 Cygni, HD 206267, ε Cephei, σ Cassiopeiae, ρ Cassiopeiae, τ Cassiopeiae, AR Cassiopeiae, 9 Lacertae, 3 Andromedae, 7 Andromedae, 8 Andromedae, λ Andromedae, κ Andromedae, ι Andromedae and ψ Andromedae. Consequently, the Chinese name for β Lacertae itself is 螣蛇十 (Téng Shé shí, English: the Tenth Star of Flying Serpent).[8]

References

[edit]
  1. ^ a b c d e f van Leeuwen, F. (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.Vizier catalog entry
  2. ^ a b c d e "bet Lac". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved November 17, 2008.
  3. ^ a b c d e f Baines, Ellyn K.; et al. (2018). "Fundamental Parameters of 87 Stars from the Navy Precision Optical Interferometer". The Astronomical Journal. 155 (1). 30. arXiv:1712.08109. Bibcode:2018AJ....155...30B. doi:10.3847/1538-3881/aa9d8b. S2CID 119427037.
  4. ^ a b c d HR 8538, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line November 17, 2008.
  5. ^ a b c Takeda, Yoichi; et al. (August 2008), "Stellar Parameters and Elemental Abundances of Late-G Giants", Publications of the Astronomical Society of Japan, 60 (4): 781–802, arXiv:0805.2434, Bibcode:2008PASJ...60..781T, doi:10.1093/pasj/60.4.781, S2CID 16258166.
  6. ^ Mishenina, T. V.; et al. (September 2006), "Elemental abundances in the atmosphere of clump giants", Astronomy and Astrophysics, 456 (3): 1109–1120, arXiv:astro-ph/0605615, Bibcode:2006A&A...456.1109M, doi:10.1051/0004-6361:20065141, S2CID 18764566.
  7. ^ 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.
  8. ^ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 7 日 Archived 2011-05-21 at the Wayback Machine