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Find the constellation Hercules between two bright stars

The bright stars Vega in the constellation Lyra and Arcturus in the constellation Bootes are located on either side of Hercules.

Tonight for April 17, 2015

On these springtime evenings, why not try locating one of the coolest constellations up there? The constellation Hercules the Kneeling Giant can be seen ascending in the east-northeast on these spring evenings. You can find Hercules in between two brilliant springtime stars: Arcturus and Vega. At nightfall, Vega may still be underneath in the horizon, look for Hercules below the star Arcturus.

By the way, Vega closely marks the radiant point of the Lyrid meteor shower. This annual April shower is expected to peak on the morning of April 22.

Everything you need to know: Lyrid meteor shower

Link to Radiant point of Lyrid shower

The radiant point of the Lyrid meteor shower is near the bright star Vega in the constellation Lyra the Harp.

The radiant point of the Lyrid meteor shower is near the bright star Vega in the constellation Lyra the Harp.

The constellation Hercules, with its prominent Keystone asterism marked.  This image is from Wikimedia Commons.  Go there to read about the star names in this constellation.

The constellation Hercules, with its prominent Keystone asterism marked. This image is from Wikimedia Commons. Go there to read about the star names in this constellation.

The chart at the top of this post shows the sky for around 10 to 11 p.m. local time, when the constellation Hercules, and the two bright stars so essential for finding it, are well up in the northeastern to eastern sky. The stars are Arcturus in the constellation Bootes and Vega in the constellation Lyra. A line between them passes through what is known as the Keystone in the constellation Hercules.

The Keystone in Hercules is a squarish figure in the center of the constellation. This sky pattern is an asterism, or noticeable pattern within a larger constellation.

The Keystone is a helpful pattern for more reasons than one. First, it’s noticeable on the sky’s dome, so can lead your eye to Hercules.

A planisphere is virtually indispensable for beginning stargazers. Order your EarthSky planisphere today.

M13, aka the Great Cluster in Hercules.  This object is a globular star cluster, oneof our galaxy's oldest inhabitants.  Photo via Bareket Observatory in Israel, via CelestronImages.

M13, aka the Great Cluster in Hercules. This object is a globular star cluster, oneof our galaxy’s oldest inhabitants. Photo via Bareket Observatory in Israel, via CelestronImages.

Also, the Keystone in Hercules can help you find the most fascinating telescopic object within the boundaries of this constellation. This object is a globular star cluster known to stargazers as M13 or the Great Cluster in Hercules. It’s barely visible the eye alone in the darkest of skies.

Binoculars show M13 as a nebulous star-like patch of light. And telescopes show stars both on the periphery of the cluster and toward its center.

This beautiful object is one of the galaxy’s oldest inhabitants. It’s a tightly packed spherical collection of about one million stars.

Bottom line: Use the brilliant stars Arcturus and Vega to find the constellation Hercules tonight!

More on M13: Great cluster in Hercules

Get your kids interested in astronomy and the sky! Use EarthSky’s lunar calendar as a fun way to enjoy the moon phases throughout the year.