Rho2 Cephei

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Template:Short description Template:Other stars by Bayer designation

Rho2 Cephei
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Cepheus
Right ascension Template:RA[1]
Declination Template:DEC[1]
Apparent magnitude (V) 5.50[2]
Characteristics
Spectral type A3 V[3]
U−B Template:Engvar +0.07[2]
B−V Template:Engvar +0.06[2]
Astrometry
Proper motion (μ) RA: +3.68[1] mas/yr
Dec.: −21.29[1] mas/yr
Parallax (π)13.31±0.21 mas[1]
DistanceTemplate:Rnd ± Template:Rnd ly
(Template:Rnd ± Template:Rnd pc)
Absolute magnitude (MV)+1.07[4]
Details
MassTemplate:Val[5] Template:Solar mass
Luminosity32[4] Template:Solar luminosity
Surface gravity (log g)4.2[6] cgs
Temperature8,511[5] K
Rotational velocity (v sin i)133[7] km/s
Age85[6] Myr
Metallicity [Fe/H]{{{metal_fe2}}} dex
Other designations
 Cephei, ρ2 Cep, 29 Cephei, BD+78°801, FK5 1593, HD 213798, HIP 111056, HR 8591, SAO 10402[8]
Database references
SIMBADdata

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Rho2 Cephei, Latinized from ρ2 Cephei, or simply ρ Cephei, is a solitary[9] star in the northern constellation of Cepheus. With an apparent visual magnitude of 5.50,[2] it is faintly visible to the naked eye, forming an optical pair with Rho1 Cephei. Based upon an annual parallax shift of 13.31 mas as seen from the Earth,[1] it is located about 245 light years from the Sun.

Rho2 Cephei is an A-type main sequence star with a stellar classification of A3 V,[3] estimated to be 85 million years old. It has a high rate of rotation, showing a projected rotational velocity of 133 km/s.[7] The effective temperature of its photosphere is Template:Val and its bolometric luminosity, the total amount of radiation it emits at all wavelengths, is Template:Solar luminosity.

References

Template:Reflist

Template:Stars of Cepheus

  1. a b c d e f Cite error: Invalid <ref> tag; no text was provided for refs named vanLeeuwen2007
  2. a b c d Cite error: Invalid <ref> tag; no text was provided for refs named Oja1983
  3. a b Cite error: Invalid <ref> tag; no text was provided for refs named Cowley1969
  4. a b Cite error: Invalid <ref> tag; no text was provided for refs named Anderson2012
  5. a b Cite error: Invalid <ref> tag; no text was provided for refs named Zorec2012
  6. a b Cite error: Invalid <ref> tag; no text was provided for refs named gullikson
  7. a b Cite error: Invalid <ref> tag; no text was provided for refs named Royer2007
  8. Cite error: Invalid <ref> tag; no text was provided for refs named SIMBAD
  9. Cite error: Invalid <ref> tag; no text was provided for refs named Eggleton2008