Rho1 Cephei
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Cepheus |
| Right ascension | 22h 26m 42.40624s[1] |
| Declination | +78° 47′ 09.0725″[1] |
| Apparent magnitude (V) | 5.84[2] |
| Characteristics | |
| Spectral type | A2m[3] |
| B−V color index | −0.16[2] |
| Astrometry | |
| Proper motion (μ) | RA: −13.33[1] mas/yr Dec.: −36.95[1] mas/yr |
| Parallax (π) | 15.83 ± 0.23 mas[1] |
| Distance | 206 ± 3 ly (63.2 ± 0.9 pc) |
| Details | |
| ρ1 Cep A | |
| Mass | 2.00[3] M☉ |
| Rotational velocity (v sin i) | 81[4] km/s |
| Age | 320[3] Myr |
| ρ1 Cep B | |
| Mass | 0.51[3] M☉ |
| Other designations | |
| Database references | |
| SIMBAD | data |
Rho1 Cephei (ρ1 Cephei) is a double star located in the northern constellation of Cepheus. As of 2014, the pair had an angular separation of 0.29 arc seconds along a position angle of 211.1°. This corresponds to a projected separation of 18.1 AU.[3] Rho1 Cephei is faintly visible to the naked eye with an apparent visual magnitude of 5.84,[2] and it forms an optical pair with the brighter star Rho2 Cephei. Based upon an annual parallax shift of 15.83 mas as seen from the Earth,[1] Rho1 Cephei is located about 206 light years from the Sun.
The primary component is a chemically peculiar Am star with a stellar classification of A2m.[3] It has twice the mass of the Sun and is around 320 million years old.[3] The smaller companion may be the source of the X-ray emission from this location, as stars similar to the primary component do not generally produce detectable levels of X-rays.[6]
References
- ^ a b c d e f van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
- ^ a b c Oja, T. (August 1991), "UBV photometry of stars whose positions are accurately known. VI", Astronomy and Astrophysics Supplement Series, 89 (2): 415–419, Bibcode:1991A&AS...89..415O.
- ^ a b c d e f g De Rosa, R. J.; et al. (2013), "The VAST Survey - III. The multiplicity of A-type stars within 75 pc", Monthly Notices of the Royal Astronomical Society, 437 (2): 1216, arXiv:1311.7141, Bibcode:2014MNRAS.437.1216D, doi:10.1093/mnras/stt1932, S2CID 88503488.
- ^ Royer, F.; et al. (October 2002), "Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i", Astronomy and Astrophysics, 393: 897–911, arXiv:astro-ph/0205255, Bibcode:2002A&A...393..897R, doi:10.1051/0004-6361:20020943, S2CID 14070763.
- ^ "rho01 Cep". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-05-05.
{cite web}: CS1 maint: postscript (link) - ^ De Rosa, R. J.; et al. (July 2011), "The Volume-limited A-Star (VAST) survey - I. Companions and the unexpected X-ray detection of B6-A7 stars", Monthly Notices of the Royal Astronomical Society, 415 (1): 854–866, arXiv:1103.4363, Bibcode:2011MNRAS.415..854D, doi:10.1111/j.1365-2966.2011.18765.x, S2CID 84181878.
