31 Comae Berenices

31 Comae Berenices
Observation data
Epoch J2000      Equinox J2000
Constellation Coma Berenices
Right ascension 12h 51m 41.91900s[1]
Declination +27° 32′ 26.5683″[1]
Apparent magnitude (V) 4.87 - 4.97[2]
Characteristics
Evolutionary stage Hertzsprung gap[3]
Spectral type G0III[4]
Variable type FK Com[2]
Astrometry
Proper motion (μ) RA: −10.990[1] mas/yr
Dec.: −8.313[1] mas/yr
Parallax (π)11.4933 ± 0.1828 mas[1]
Distance284 ± 5 ly
(87 ± 1 pc)
Details[4]
Radius8.9 R☉
Luminosity74 L☉
Surface gravity (log g)3.51 cgs
Temperature5,660 K
Metallicity [Fe/H]−0.15 dex
Rotation6.8 d
Rotational velocity (v sin i)67 km/s
Other designations
31 Com, LS Comae Berenices, BD+28°2156, FK5 1332, HD 111812, HIP 62763, HR 4883, SAO 82537[5]
Database references
SIMBADdata

31 Comae Berenices (31 Com) is a yellow giant star in the constellation Coma Berenices. Its apparent magnitude is about 4.9 and slightly variable. It is a rare FK Comae Berenices variable, a variable star that spins rapidly and has large starspots on its surface.[5] It is currently in the Hertzsprung gap and its outer envelope has just begun convection.[3] In 1989 it was given as a spectral standard for the class G0IIIp.[6]

31 Com is the north galactic pole star, and occasionally goes by the informal name Polaris Galacticum Borealis, coined by Jim Kaler.[7]

In Chinese astronomy, 31 Comae Berenices is called 郎將, Pinyin: Lángjiāng, meaning Captain of the Bodyguards, because this star is marking itself and stand alone in Captain of the Bodyguards asterism, Supreme Palace enclosure mansion (see : Chinese constellation).[8]

  1. ^ a b c d e Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference gcvs was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Strassmeier2010 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Auriere2015 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference perkins was invoked but never defined (see the help page).
  7. ^ "Polaris Galacticum Borealis". Retrieved 2015-12-02.
  8. ^ Ian Ridpath's Startales - Coma Berenices the Berenice's Hair