A small but prominent constellation in the northern hemisphere, listed by Ptolemy (c. AD 140). Its brightest star, Vega, is zero magnitude and the fifth-brightest star in the sky. There are three other stars brighter than fourth magnitude. Epsilon Lyrae is a noted 'double double', consisting of a widely spaced pair of close double stars. Lyra also includes one of the best-known of all planetary nebula, the Ring Nebula.
