14 Comae Berenices

14 Comae Berenices is a single^[3] star in the northern constellation of Coma Berenices, and is the second brightest^[8] member of the Coma Star Cluster.^[3] It is a faint star but visible to the naked eye with an apparent visual magnitude of 4.95.^[2] Parallax measurements place the star at a distance of about 266 light years.^[1]

14 Comae Berenices

Location of 14 Com (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Coma Berenices
Right ascension	12h 26m 24.06461s[1]
Declination	+27° 16′ 05.6845″[1]
Apparent magnitude (V)	4.95[2]
Characteristics
Spectral type	F0p[3][4]
U−B color index	+0.18[2]
B−V color index	+0.277±0.018[5]
Astrometry
Radial velocity (Rv)	−2.20[6] km/s
Proper motion (μ)	RA: −16.010[1] mas/yr Dec.: −13.412[1] mas/yr
Parallax (π)	12.2564±0.2329 mas[1]
Distance	266 ± 5 ly (82 ± 2 pc)
Absolute magnitude (MV)	+0.35[7]
Details[8]
Mass	2.4[7] M☉
Radius	23 R☉
Luminosity	76.01[5] L☉
Surface gravity (log g)	3.4[8] cgs
Temperature	7,300 K
Rotational velocity (v sin i)	226[7] km/s
Age	500 Myr
Other designations
14 Com, AAVSO 1221+27, BD+28°2115, FK5 2997, HD 108283, HIP 60697, HR 4733, SAO 82310[9]
Database references
SIMBAD	data

The spectrum of this star is peculiar and it has been assigned a number of different stellar classifications: A5, F0p, F0 III Sr, F0 vp,^[3] F1 IV: np Sr shell,^[5] A9 IV np Sr II,^[10] F1 IV,^[11] and A9 V + shell.^[12] Abt & Morrell (1995) designated this a Lambda Boötis star but this was later refuted.^[10] No surface magnetic field has been detected on 14 Comae Bernices.^[13]

14 Comae Berenices is a well-known^[12][8] shell star with a high rate of spin, showing a projected rotational velocity of 226 km/s.^[7] This is giving the star an oblate shape with an equatorial bulge that is 12% larger than the polar radius.^[4] It is radiating 76^[5] times the Sun's luminosity from its photosphere at an effective temperature of 7,300 K.^[8]