The three brightest stars in the picture form the so- called Summer Triangle, consisting of Deneb (upper left) in the constellation of Cygnus, Vega (centre right) in Lyra, and Altair (bottom left) in Aquila. The nickname is only appropriate in the northern hemisphere; in the south, the three stars are best seen in winter. Vega is the fifth brightest star in the sky. Deneb, located some 1800 light-years away, is 70,000 times as powerful as our Sun. Altair is only 10 times as luminous as the Sun, but is much closer at a distance of only 16. 6 light-years. 24mm, f/4.