Messier 13 or M13, also known as the Hercules Cluster, is a very bright globular cluster in the constellation Hercules. It contains at least 500,000 stars. The star cluster is about 25,000 light years away and consists of about 500,000 suns. The Arecibo message was sent in this direction in 1974 (en.wikipedia.org/wiki/Arecibo_message), revealing, among other things, where the Earth is and that there is life here. Whether this was a good idea will perhaps be revealed to our descendants in 50,000 years' time, provided our Earth will still be a habitable planet by then.
