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In a dark sky, look for the Northern Crown


Tonight for May 21, 2014

Corona Borealis

Corona Borealis, the Northern Crown, as pointed out with a green laser pointer by Jan Wojcik, director of Reynolds Observatory. Image Credit: Kyle Foley

There’s a constellation on this chart that’s easy to see on the sky’s dome, if your sky is dark enough. Corona Borealis – doesn’t look like much on this chart, but in a dark sky it’s exciting to find – an almost-perfect semi-circle of stars.

Corona Borealis is also known as the Northern Crown. It’ll adorn the evening sky from now until October.

The constellation Corona Borealis is located more or less along a line between two bright stars, Arcturus in the constellation Bootes the Herdsman and Vega in the constellation Lyra the Harp. In the east-northeast in mid-evening, you’ll see Arcturus fairly high in the east, noticeable for its brightness and yellow-orange color. Vega will be low on the northeastern horizon – bright and blue-white in color. The Northern Crown is more or less between these two bright stars. It’s a semi-circle of stars – very noticeable in a dark sky.

Corona Borealis

The C-shaped constellation Corona Borealis shines between the constellations Bootes and Hercules. View larger

Alphecca: Northern Crown’s Brightest Star

The brightest star in Corona Borealis is Alphecca, also known as Gemma, sometimes called the Pearl of the Crown. The name Alphecca originated with a description of Corona Borealis as the “broken one,” in reference to the fact that these stars appear in a semi-circle, rather than a full circle. Alphecca is a blue-white star, with an intrinsic luminosity some 60 times that of our sun. It’s located about 75 light-years from Earth.

Stellar luminosity: The true brightnesses of stars

Look for the Northern Crown between the brilliant stars Arcturus and Vega tonight!