22_Boötis
22 Boötis
Star in the constellation Boötes
22 Boötis is a single[6] star in the northern constellation of Boötes,[5] located 319 light years away from the Sun.[1] It has the Bayer designation f Boötis; 22 Boötis is the Flamsteed designation.[5] This object is visible to the naked eye as a dim, white-hued star with an apparent visual magnitude of 5.40.[2] It is moving closer to the Earth with a heliocentric radial velocity of −27 km/s.[2]
This is an Am star[7] with a stellar classification of kA7 hA8 mF2 (III) ((Sr II)),[3] 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.[7] The star has twice[4] the mass of the Sun and four[1] times the Sun's radius. It is spinning with a projected rotational velocity of 38[2] km/s. 22 Boötis is radiating 52[1] times the Sun's luminosity from its photosphere at an effective temperature of 7,528 K.[1]