25 Canum Venaticorum

25 Canum Venaticorum
Observation data
Epoch J2000      Equinox J2000
Constellation Canes Venatici
Right ascension 13h 37m 27.62782s[1]
Declination +36° 17′ 41.6337″[1]
Apparent magnitude (V) +4.82[2] (4.98 + 6.95)[3]
Characteristics
Spectral type A7 III + A8 V:[4]
Astrometry
Radial velocity (Rv)−10.4±2.1[2] km/s
Proper motion (μ) RA: −95.54[1] mas/yr
Dec.: +23.75[1] mas/yr
Parallax (π)16.42 ± 0.53 mas[1]
Distance199 ± 6 ly
(61 ± 2 pc)
Absolute magnitude (MV)0.90[2]
Orbit[5]
Period (P)228 yr
Semi-major axis (a)1.02″
Eccentricity (e)0.80
Inclination (i)147°
Longitude of the node (Ω)87°
Periastron epoch (T)1864.0
Argument of periastron (ω)
(secondary)		159°
Details
25 CVn A
Mass2.23[6] M☉
Surface gravity (log g)3.85[7] cgs
Temperature7,609±259[7] K
Rotational velocity (v sin i)235[8] km/s
Age659[7] Myr
25 CVn B
Mass1.58[6] M☉
Other designations
25 CVn, BD+37° 2433, FK5 3083, GC 18421, HD 118623, HIP 66458, HR 5127, SAO 63648, ADS 8974, CCDM 13375+3617, WDS J13375+3618[9]
Database references
SIMBADdata

25 Canum Venaticorum is a binary star[10] system in the northern constellation of Canes Venatici, approximately 199[1] light years from the Sun. It is visible to the naked eye as a faint, white-hued star with a combined apparent visual magnitude of +4.82[2] The system is moving closer to the Earth with a heliocentric radial velocity of roughly −10 km/s.[2]

This is a wide binary system with an orbital period of 228 years and an eccentricity of 0.80.[5] As of 2001, they had a projected separation of 107.0 AU.[6] The magnitude 4.98[3] primary, component A, has a stellar classification of A7 III,[4] which matches an A-type giant star. It is 659[7] million years old with a projected rotational velocity of 235 km/s. This rate of spin is giving the star an oblate shape with an equatorial bulge that is an estimated 27% larger than the polar radius.[8] The companion, component B, is a magnitude 6.95[3] A-type main-sequence star with a class of A8 V:.[4] The ':' suffix indicates some uncertainty in the classification of this star.

  1. ^ a b c d e f Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  3. ^ a b c Cite error: The named reference wds was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference Stephenson1969 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Soderhjelm1999 was invoked but never defined (see the help page).
  6. ^ a b c Cite error: The named reference DeRosa2014 was invoked but never defined (see the help page).
  7. ^ a b c d Cite error: The named reference David2015 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference vanBelle2012 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).