Arkab Posterior is a white subgiant star in the constellation Sagittarius. At 134 light years away, it shines at an apparent visual magnitude of 4.27. The star's age is estimated to be 1 billion years but is certainly no less than 900 million years and no greater than 1.1 billion years. The iron abundance of Arkab Posterior is -0.17 (67.6% of the Sun). It is moving through the Galaxy at a speed of 28.4 km/s relative to the Sun. Its projected Galactic orbit carries it between 22,800 and 30,000 light years from the center of the Galaxy. It came closest to the Sun 949,000 years ago when it had brightened to magnitude 3.62 from a distance of 100 light years.
Sky position: RA 19h 23.2m, Dec -44° 48'
Common designations: Arkab Posterior, Beta-2 Sagittarii, HIP 95294, HD 181623, HR 7343