V Cephei

V Cephei is a white main sequence star in the constellation Cepheus. It only varies slightly by 0.03 of a magnitude. It was suspected of being variable by American astronomer Seth Carlo Chandler noting in 1890 that it varied by 0.7 magnitude but that it needed more confirmation. Subsequent observers were divided in whether they noted variability or not.^[9] A subsequent study with photoelectric photometry showed no variability.^[10]

V Cephei

Observation data Epoch J2000      Equinox J2000
Constellation	Cepheus
Right ascension	23h 56m 27.804s[1]
Declination	+83° 11′ 28.02″[1]
Apparent magnitude (V)	6.57[2]
Characteristics
Spectral type	A1V[3]
B−V color index	+0.07[2]
Astrometry
Radial velocity (Rv)	−18.74[1] km/s
Proper motion (μ)	RA: +50.676[1] mas/yr Dec.: +6.869[1] mas/yr
Parallax (π)	11.1865 ± 0.0264 mas[1]
Distance	291.6 ± 0.7 ly (89.4 ± 0.2 pc)
Absolute magnitude (MV)	+1.78[4]
Details
Mass	2.27[5] M☉
Radius	1.7[5] R☉
Luminosity	17.4[5] L☉
Surface gravity (log g)	4.33[5] cgs
Temperature	9,004[5] K
Metallicity [Fe/H]	−0.25[6] dex
Rotational velocity (v sin i)	147[7] km/s
Age	373[7] Myr
Other designations
V Cep, BD+82°743, FK5 1650, HD 224309, HIP 118027, HR 9056, SAO 3994[8]
Database references
SIMBAD	data

With a spectral class of A1V, V Cephei is a main sequence star with a surface temperature of 9,004 K. It has twice the mass of the Sun and, with nearly twice its radius, it shines at 17 L_☉.

References

1. 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.
2. Oja, T. (August 1991). "UBV photometry of stars whose positions are accurately known. VI". Astronomy and Astrophysics Supplement Series. 89: 415. Bibcode:1991A&AS...89..415O. ISSN 0365-0138.
3. Abt, Helmut A.; Morrell, Nidia I. (1995). "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars". Astrophysical Journal Supplement. 99: 135. Bibcode:1995ApJS...99..135A. doi:10.1086/192182.
4. 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.
5. Stassun, Keivan G.; et al. (2019-10-01). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467. hdl:1721.1/124721. ISSN 0004-6256. S2CID 166227927.
6. Anders, F.; Khalatyan, A.; Chiappini, C.; Queiroz, A. B.; Santiago, B. X.; Jordi, C.; Girardi, L.; Brown, A. G. A.; Matijevič, G.; Monari, G.; Cantat-Gaudin, T.; Weiler, M.; Khan, S.; Miglio, A.; Carrillo, I.; Romero-Gómez, M.; Minchev, I.; De Jong, R. S.; Antoja, T.; Ramos, P.; Steinmetz, M.; Enke, H. (2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy and Astrophysics. 628: A94. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. S2CID 131780028.
7. David, Trevor J.; Hillenbrand, Lynne A. (2015). "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal. 804 (2): 146. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146. S2CID 33401607.
8. "V* V Cep". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved August 17, 2010.
9. Hoffleit, Dorrit (1985). "Was Harlow Shapley Right About V Cephei?". The Journal of the American Association of Variable Star Observers. 14 (2): 64–66. Bibcode:1985JAVSO..14...64H.
10. Fortier, George (1989). "Photoelectric Photometry of V Cephei". The Journal of the American Association of Variable Star Observers. 18 (1): 49–51. Bibcode:1989JAVSO..18...49F.