22 Boötis

22 Boötis
Observation data
Epoch J2000      Equinox J2000
Constellation Boötes
Right ascension 14h 26m 27.36529s
Declination +19° 13 36.8470
Apparent magnitude (V) 5.40
Characteristics
Spectral type kA7hA8mF2(III)((Sr II))
B−V color index 0.231±0.006
Astrometry
Radial velocity (Rv)−27.4±0.5 km/s
Proper motion (μ) RA: –70.131 mas/yr
Dec.: +26.084 mas/yr
Parallax (π)10.2279±0.1491 mas
Distance319 ± 5 ly
(98 ± 1 pc)
Absolute magnitude (MV)0.65
Details
Mass1.99±0.02 M
Radius4.03+0.23
−0.26
 R
Luminosity52.43±0.89 L
Surface gravity (log g)3.13±0.52 cgs
Temperature7,528+277
−207
 K
Metallicity [Fe/H]+0.36±0.04 dex
Rotational velocity (v sin i)37.74±2.12 km/s
Other designations
f Boo, 22 Boo, BD+19°2810, FK5 1378, GC 19480, HD 126661, HIP 70602, HR 5405, SAO 101025
Database references
SIMBADdata

22 Boötis is a single star in the northern constellation of Boötes, located 319 light years away from the Sun. It has the Bayer designation f Boötis; 22 Boötis is the Flamsteed designation. This object is visible to the naked eye as a dim, white-hued star with an apparent visual magnitude of 5.40. It is moving closer to the Earth with a heliocentric radial velocity of −27 km/s.

This is an Am star with a stellar classification of kA7 hA8 mF2 (III) ((Sr II)), showing the calcium K line of an A7 star, the hydrogen lines of an A8 star, and the metal lines of an F2 star. It has the luminosity class of a giant star and does not appear to be variable. The star has twice the mass of the Sun and four times the Sun's radius. It is spinning with a projected rotational velocity of 38 km/s. 22 Boötis is radiating 52 times the Sun's luminosity from its photosphere at an effective temperature of 7,528 K.