Messier 13 – Great Globular Cluster in Hercules

Constellation: Hercules
Distance: 25,100 light years
Apparent Magnitude: 5.8
Actual Size: 145 light years across
Visual Size: 20 arcminutes
Other Designations: NGC 6205

Discovered by Edmond Halley in 1714. Barely visible to the naked eye, but easily viewable in a small telescope, this beautiful cluster is comprised of over 300,000 stars.

Messier 13 is easy to spot in images due to the dark 3 pronged ‘propeller’. Nearby, NGC6207 is a 12th magnitude galaxy which is often captured in images of M13.

In 1974, the Arecibo Radio Telescope in Puerto Rico directed a message at Messier 13. Unfortunately, by the time the message arrives, the motion of Messier 13 around our galaxy means we will miss!