Beta Lacertae

β Lacertae

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Lacerta
Right ascension	22^h 23^m 33.6235^s[1]
Declination	+52° 13′ 44.567″[1]
Apparent magnitude (V)	4.43[1]
Characteristics
Spectral type	G8.5IIIb[1]
U−B color index	+0.77[2]
B−V color index	+1.02[2]
V−R color index	0.6[1]
R−I color index	+0.57[2]
Astrometry
Radial velocity (Rv)	−10.4 ± 0.9[1] km/s
Proper motion (μ)	RA: −13.56[1] mas/yr Dec.: −186.37[1] mas/yr
Parallax (π)	19.21 ± 0.51[1] mas
Distance	170 ± 5 ly (52 ± 1 pc)
Absolute magnitude (MV)	0.85[3]
Details
Radius	10.7 ± 0.3[4] R☉
Rotational velocity (v sin i)	< 17[2] km/s
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.[1]
Database references
SIMBAD	data

Beta Lacertae (Beta Lac, β Lacertae, β Lac) is the fourth brightest star in the constellation of Lacerta. It is a G-type giant with an apparent visual magnitude of approximately 4.43.^[1]

Naming

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, β Lacertae itself is known as 螣蛇十 (Téng Shé shí, English: the Tenth Star of Flying Serpent)^[5]

References

1. NLTT 53741 -- High proper-motion Star, database entry, SIMBAD. Accessed on line November 17, 2008.
2. 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.
3. From apparent magnitude and parallax.
4. Nordgren, Tyler E.; et al. (December 1999), "Stellar Angular Diameters of Late-Type Giants and Supergiants Measured with the Navy Prototype Optical Interferometer", The Astronomical Journal 118 (6): 3032–3038, Bibcode:1999AJ....118.3032N, doi:10.1086/301114
5. (Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 7 日