Instead of turning on the TV tonight, why not turn to the eastern sky about two hours after sundown and see if you can spot the famous “Summer Triangle.”
Joe Rao, Farmers’ Almanac Astronomer, tells us that this time of year is the best time to see the famous “Summer Triangle.” “You can’t miss it because the triangle is composed of three of the brightest stars in the sky, each of which is the brightest star in its own constellation,” shares Rao.
The brightest is the bluish-white star Vega, in Lyra the Lyre. Next in brightness is yellow-white Altair in Aquila, the Eagle. Finally there is white Deneb, in Cygnus, the Swan.
From our viewpoint, Vega appears twice as bright as Altair and more than three times brighter than Deneb. But sometimes things are not always what they seem. Astronomers know, for instance, that Vega clearly is more luminous compared to Altair, because it’s situated at a greater distance from us. Altair is 17 light years away, while Vega is 25. The light you see from Vega tonight started on its journey to Earth in 1983.
Vega actually pales in comparison with Deneb, one of the greatest supergiant stars known. Deneb’s distance measures 1,467 light years from Earth, with a luminosity computed to be more than 80,000 times that of our Sun. But because its light takes nearly 15 centuries to reach us, Deneb merely appears as a fairly conspicuous but by no means particularly notable star.
Check it out. Tonight when the sky is dark, see if you can spot this triangle.