19_Arietis
19 Arietis
Star in the constellation Aries
19 Arietis (abbreviated 19 Ari) is a star in the northern constellation of Aries. 19 Arietis is the Flamsteed designation. It has an apparent visual magnitude of 5.70,[2] which means it is faintly visible to the naked eye. Based upon an annual parallax shift of 6.81 mas,[1] it is approximately 480 light-years (150 parsecs) away from Earth. At that distance, the brightness of the star is diminished by 0.21 in magnitude from extinction caused by interstellar gas and dust.[5]
This is a red giant star with a stellar classification of M0 III.[3] It is a semi-regular variable with periods of 32 and 275 days; the brightness of the star changes by an amplitude of 0.14 in magnitude during those intervals.[4] The measured angular diameter of this star, after correction for limb darkening, is 2.44 ± 0.03 mas.[10] At the estimated distance,[1] this yields a physical size of about 39 times the radius of the Sun.[6] The effective temperature of the outer envelope is 3,690 K,[7] giving it the cool reddish glow of an M-type star.[11]