21 Comae Berenices
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Coma Berenices |
| Right ascension | 12h 31m 00.561s |
| Declination | +24° 34′ 01.80″ |
| Apparent magnitude (V) | 5.47 or 5.41 – 5.46 |
| Characteristics | |
| Evolutionary stage | main sequence |
| Spectral type | A3p SrCr |
| B−V color index | 0.056±0.008 |
| Variable type | α2 CVn + δ Sct |
| Astrometry | |
| Radial velocity (Rv) | +1.0±1.8 km/s |
| Proper motion (μ) | RA: −12.474 mas/yr Dec.: −9.085 mas/yr |
| Parallax (π) | 12.0785±0.1214 mas |
| Distance | 270 ± 3 ly (82.8 ± 0.8 pc) |
| Absolute magnitude (MV) | 0.66 |
| Details | |
| Mass | 2.29±0.10 M☉ |
| Radius | 2.6±0.2 R☉ |
| Luminosity | 38.2±1.3 L☉ |
| Surface gravity (log g) | 3.9±0.2 cgs |
| Temperature | 8,900±200 K |
| Rotation | 2.05219 d |
| Rotational velocity (v sin i) | 63±2 km/s |
| Age | 400–800 Myr |
| Other designations | |
| Kissīn, 21 Com, UU Com, BD+25°2517, HD 108945, HIP 61071, HR 4766, SAO 82346 | |
| Database references | |
| SIMBAD | data |
21 Comae Berenices is a variable star in the northern constellation of Coma Berenices. It has the variable star designation UU Comae Berenices, while 21 Comae Berenices is the Flamsteed designation.