Δ_Arae
Delta Arae
Star in the constellation Ara
Delta Arae, Latinized from δ Arae, is the Bayer designation for a double star in the southern constellation Ara. It has an apparent visual magnitude of 3.62[2] and is visible to the naked eye. Based upon an annual parallax of 16.48 mas, it is about 198 light-years (61 parsecs) distant from the Earth.[1]
Delta Arae is massive B-type main sequence star with a stellar classification of B8 Vn.[3] The 'n' suffix indicates the absorption lines are spread out broadly because the star is spinning rapidly. It has a projected rotational velocity of 255 km/s, resulting in an equatorial bulge with a radius 13% larger than the polar radius.[4] It has a magnitude 9.5 companion G-type main sequence star that may form a binary star system with Delta Arae.[7]
There is a 12th magnitude optical companion located 47.4 arcseconds away along a position angle of 313°.[9]