Categories
Zeta Cephei
Topic: Astronomy
From HandWiki - Reading time: 5 min
  | |
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Cepheus |
| Right ascension | 22h 10m 51.277s[1] |
| Declination | +58° 12′ 04.54″[1] |
| Apparent magnitude (V) | 3.35[2] |
| Characteristics | |
| Evolutionary stage | Red supergiant[3] |
| Spectral type | K1.5 Ib[4] |
| B−V color index | +1.55[2] |
| Astrometry | |
| Proper motion (μ) | RA: 13.359±0.148[1] mas/yr Dec.: 5.275±0.183[1] mas/yr |
| Parallax (π) | 3.2972 ± 0.1456[1] mas |
| Distance | 992.7+51.2 −46 ly (304.5+15.7 −14.1 pc) |
| Absolute magnitude (MV) | −4.7[3] |
| Details | |
| Mass | 10.1±0.1[5] M☉ |
| Radius | 172.7+7.5 −8.3[6] R☉ |
| Luminosity | 10,024±1,052[6] L☉ |
| Surface gravity (log g) | 0.75[7] cgs |
| Temperature | 4,393±58[6] K |
| Metallicity [Fe/H] | +0.04[6] dex |
| Rotational velocity (v sin i) | 10.64[8] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
Zeta Cephei is a red supergiant star in the northern constellation of Cepheus. Its name is a Bayer designation that is Latinized from ζ Cephei, and abbreviated Zeta Cep or ζ Cep. With an apparent visual magnitude of 3.35,[2] it is a third-magnitude star that is visible to the naked eye. Based on parallax measurements, it is located about 1000 light-years away from the Earth. Zeta Cephei marks the left shoulder of Cepheus, a mythical King of Aethiopia. It is one of the fundamental stars of the MK spectral sequence, defined as type K1.5 Ib.
Characteristics
Zeta Cephei has a spectral classification of K1.5Ib,[4] indicating that it is a lower luminosity red supergiant star. It is about 173 times larger than the Sun and has a surface temperature of 4,393 K.[6] The luminosity of Zeta Cephei is approximately 10,000 times that of the Sun.[6] At a distance of about 840 light-years,[10] Zeta Cephei has an apparent magnitude (m) of 3.4 and an absolute magnitude (M) of -3.7.[11] The star has a metallicity similar to the Sun.[6]
At a mass of 10.1 M☉, Zeta Cephei might end its life in a core-collapse supernova, and has been listed as a likely pre-supernova candidate by a 2022 study. It could also provide observable pre-supernova neutrino signals, just hours before the core collapses.[5]
Hekker et al. (2008) have detected a periodicity of 533 days, hinting at the possible presence of an as yet unseen companion.[12] It is listed as a candidate eclipsing binary with a very small amplitude.[13] However, spectroscopic measurements made from 1993 to 2015 do not support the presence of the companion.[11]
References
- ↑ 1.0 1.1 1.2 1.3 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 Ducati, J. R. (2002-01-01). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system.". VizieR Online Data Catalog 2237. Bibcode: 2002yCat.2237....0D. https://ui.adsabs.harvard.edu/abs/2002yCat.2237....0D. Zeta Cephei's database entry at VizieR.
- ↑ 3.0 3.1 Luck, R. E. (1982). "The chemical composition of late-type supergiants. IV - Homogeneous abundances and galactic metallicity trends". Astrophysical Journal 256: 177. doi:10.1086/159895. Bibcode: 1982ApJ...256..177L.
- ↑ 4.0 4.1 Morgan, W. W.; Keenan, P. C. (1973). "Spectral Classification". Annual Review of Astronomy and Astrophysics 11: 29–50. doi:10.1146/annurev.aa.11.090173.000333. Bibcode: 1973ARA&A..11...29M.
- ↑ 5.0 5.1 Machado, L. N. et al. (2022-08-12). "Pre-supernova Alert System for Super-Kamiokande" (in en). The Astrophysical Journal 935 (1): 40. doi:10.3847/1538-4357/ac7f9c. ISSN 0004-637X. Bibcode: 2022ApJ...935...40M.
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 Baines, Ellyn K. et al. (November 2021). "Angular Diameters and Fundamental Parameters of Forty-Four Stars from the Navy Precision Optical Interferometer". The Astronomical Journal 162 (5): 198. doi:10.3847/1538-3881/ac2431. ISSN 0004-6256. Bibcode: 2021AJ....162..198B.
- ↑ Mallik, Sushma V. (December 1999). "Lithium abundance and mass". Astronomy and Astrophysics 352: 495–507. Bibcode: 1999A&A...352..495M.
- ↑ Hekker, S.; Meléndez, J. (2007). "Precise radial velocities of giant stars. III. Spectroscopic stellar parameters". Astronomy and Astrophysics 475 (3): 1003. doi:10.1051/0004-6361:20078233. Bibcode: 2007A&A...475.1003H.
- ↑ "zet Cep". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=zet+Cep.
- ↑ van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode: 2007A&A...474..653V. http://www.aanda.org/articles/aa/full/2007/41/aa8357-07/aa8357-07.html.Vizier catalog entry
- ↑ 11.0 11.1 R. F., Griffin (April 2015). "Spectroscopic binary orbits from photoelectric radial velocities. Paper 241: HR 1884, HD 174103, HD 182563, and HR 8442, with a note on zeta Cephei" (in en). The Observatory 135. ISSN 0029-7704. Bibcode: 2015Obs...135...71G.
- ↑ Hekker (2008). "Precise radial velocities of giant stars. IV. A correlation between surface gravity and radial velocity variation and a statistical investigation of companion properties". Astronomy and Astrophysics 480 (1): 215–222. doi:10.1051/0004-6361:20078321. Bibcode: 2008A&A...480..215H.
- ↑ Samus, N. N. et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007–2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S 1: 02025. Bibcode: 2009yCat....102025S.
Cite error: <ref> tag with name "b-j" defined in <references> is not used in prior text.
 |  |
EncycloReader
is supported by the 
KSF