Aquila, which occupies most of the center of the picture, is best marked by bright (first magnitude) Altair at left center, the star flanked by two outliers (Alshain below, and Tarazed above), which together give the sense of the flying Eagle. The three stars are actually depicted as marking the Eagle's back and neck. A curved line passing dowward through the three stars passes through Eta Aquilae; Delta is the second modestly bright star to the right of Delta. The Eagle's tail is indicated by the two stars at upper right that together are called Deneb al Okab (Zeta on the bottom, Epsilon on top). Altair lies at the southern apex of the Summer Triangle. Serpens (Serpens Cauda) ends at Alya, seen at upper right. In December of 1999, the constellation was graced by a naked eye nova.