4 Lacertae
| 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.
References
[edit]- ^ a b c d e f g Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c d e Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
- ^ a b c Yüce, Kutluay (2005), "Spectral Analysis of 4 Lacertae and ν Cephei", Baltic Astronomy, 14: 51–82, Bibcode:2005BaltA..14...51Y.
- ^ a b Gray, R. O.; Garrison, R. F. (1987), "The Early A-Type Stars: Refined MK Classification, Confrontation with Stroemgren Photometry, and the Effects of Rotation", The Astrophysical Journal Supplement Series, 65: 581, Bibcode:1987ApJS...65..581G, doi:10.1086/191237.
- ^ a b Kaltcheva, Nadia (October 2009), "Lacerta OB1 Revisited", Publications of the Astronomical Society of the Pacific, 121 (884): 1045–1053, Bibcode:2009PASP..121.1045K, doi:10.1086/606037, S2CID 120329065.
- ^ a b c d e f g h Markova, N.; Puls, J. (2008), "Bright OB stars in the Galaxy. IV. Stellar and wind parameters of early to late B supergiants", Astronomy and Astrophysics, 478 (3): 823, arXiv:0711.1110, Bibcode:2008A&A...478..823M, doi:10.1051/0004-6361:20077919, S2CID 14510634
- ^ Gáspár, András; et al. (2016), "The Correlation between Metallicity and Debris Disk Mass", The Astrophysical Journal, 826 (2): 171, arXiv:1604.07403, Bibcode:2016ApJ...826..171G, doi:10.3847/0004-637x/826/2/171, S2CID 119241004.
- ^ a b c Tetzlaff, N.; et al. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410 (1): 190–200, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x, S2CID 118629873.
- ^ "4 Lac". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-01-28.
- ^ Eggleton, P. P.; Tokovinin, A. A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
