Mu2_Gruis
Mu2 Gruis
Star in the constellation Grus
Mu2 Gruis, Latinized from μ2 Gruis, is a yellow-hued star or star system in the southern constellation of Grus. It is a suspected astrometric binary, showing a variation in proper motion due to gravitational acceleration.[7] Mu2 Gruis is visible to the naked eye with an apparent visual magnitude of 5.10.[2] The distance to this system, as determined using an annual parallax shift of 13.2 mas as seen from the Earth,[1] is around 248 light years. It is drifting further away with a heliocentric radial velocity of +12.5 km/s.[4]
The primary component is an evolved giant star with a stellar classification of G8 III.[3] It is a periodic variable star, showing a change in brightness with an amplitude of 0.004 magnitude at the rate of 7.50983 times per day.[8] With the supply of hydrogen at its core exhausted, the star has cooled and expanded until now it has 10 times the radius of the Sun. It is radiating 56[1] times the luminosity of the Sun from its swollen photosphere at an effective temperature of 5,009 K.[1]