As summer nears its end, the starry Summer Triangle completes its months-long climb to the summit of the sky and floats sprawling across the zenith after dark.
The Summer Triangle consists of Vega, Deneb, and Altair, three of the brightest distant suns shining over the Earth. Face south after nightfall and look up. The first you’ll spot is Altair. Now crane your neck. Brighter Vega and slightly less-bright Deneb are nearly straight up, with Deneb left of Vega. The triangle they make is three or four fists tall at arm’s length.
All three stars represent bird constellations, or parts of birds, circling in late summer. With a little imagination you can see for yourself. Full story for BostonGlobe.com subscribers.