Little Constellations
If you look into the dark sky tonight, you'll see plenty of stars, the Milky Way, and maybe even a galaxy. You won't see any borders separating one constellation from another -- but they're there. Three-quarters of a century ago, astronomers established official borders for the 88 constellations. The borders split the sky into distinct regions, just as lines on a map of the United States split it into states.
A lineup of small constellation "states" climbs high across the sky this month -- including two that are among the Rhode Islands of the cosmos.
The easiest one to spot is Lyra, the harp, because it contains Vega, one of the brightest stars in the night sky. It stands high overhead at nightfall.
Vega forms one point of the Summer Triangle. The others are Deneb, to its northeast, and Altair, to the southeast. And four small constellation run from Lyra down between these bright stars.
Starting at Lyra and moving toward the southeast, they're Vulpecula, the fox; Sagitta, the arrow; Delphinus, the dolphin; and Equuleus, the colt. Equuleus is the second-smallest constellation, while Sagitta ranks third.
For the most part, these constellations are just there to fill the space between more prominent ones. An exception is Delphinus, which really does look like a dolphin. So even though it's tiny, it's fairly easy to see -- a graceful dolphin swimming through the fringes of the Milky Way, fenced in by its own tiny borders.
Script by Damond Benningfield, Copyright 2007
For more skywatching tips, astronomy news, and much more, read StarDate magazine.
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