Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Lacerta |
Right ascension | 22h 24m 30.99149s[1] |
Declination | +49° 28′ 35.0106″[1] |
Apparent magnitude (V) | 4.55[2] |
Characteristics | |
Evolutionary stage | Blue supergiant (blue loop)[3] |
Spectral type | A0 Ib[4] |
B−V color index | 0.092±0.034[2] |
Astrometry | |
Radial velocity (Rv) | −26.0±1.7[2] km/s |
Proper motion (μ) | RA: −5.274(82)[1] mas/yr Dec.: −3.303(96)[1] mas/yr |
Parallax (π) | 1.2656 ± 0.0891 mas[1] |
Distance | 2,600 ± 200 ly (790 ± 60 pc) |
Absolute magnitude (MV) | −4.42[5] |
Details | |
Mass | 19+13 −8[6] M☉ |
Radius | 59[6] R☉ |
Luminosity | 62,000[6] L☉ |
Surface gravity (log g) | 2.18[6] cgs |
Temperature | 11,800[6] K |
Metallicity [Fe/H] | 0.28±0.04[7] dex |
Rotational velocity (v sin i) | 28±3[6] km/s |
Age | 25.1±2.5[8] Myr |
Other designations | |
Database references | |
SIMBAD | data |
4 Lacertae is a single[10] blue supergiant star in the northern constellation Lacerta, located about 2,600 light years away.[1] This object visible to the naked eye as a white-hued star with an apparent visual magnitude of 4.55.[2] It is moving closer to the Earth with a heliocentric radial velocity of −26 km/s.[2] This star is a suspected member of the Lac OB1 association.[3][5]
This blue supergiant star has a stellar classification of A0 Ib.[4] The surface abundances show evidence of material that has been processed via the CNO cycle at the core.[3] It has ten[8] times the mass of the Sun and has expanded to about 59[6] times the Sun's radius. The star is around 25[8] million years old and is spinning with a projected rotational velocity of 28 km/s.[6][1] It is believed to be a blue loop star that has already spent time as a red supergiant after fusing the hydrogen within its core.
Gaia DR3
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was invoked but never defined (see the help page).Yüce2005
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was invoked but never defined (see the help page).Tetzlaff2011
was invoked but never defined (see the help page).SIMBAD
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was invoked but never defined (see the help page).