The remarkable Hercules mass (M13, Ngc 6205), also called the 'Great globular mass in Hercules' is possibly the most illustrious globular mass residing in the Milky Way's halo. It is an additional one gigantic jewel which is viewed best either using binoculars or a small telescope.
It was discovered by Edmond Halley in 1714, who noted that 'it shows itself to the naked eye when the sky is serene and the Moon absent.' Charles Messier catalogued this beautiful object in 1764. At magnitude +5.8, it is possible from a dark site to inspect it with the naked eye as a faint smudge of light.
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When you look at this group of several hundred thousand stars (some astronomers intuit over a million!) it is marvelous to think that it is over 25,000 light years away -- and it's still just on the outskirts of our galaxy!
M13 lies in the lower left shoulder in the constellation of Hercules, which itself lies between Bootes, Corona Borealis and Lyra, and is currently best seen in the late evening/early morning in mid northern latitudes.
Towards the centre of the cluster, the stars are about five hundred times more concentrated than in our solar neighbourhood. Such globular clusters contain some of the oldest stars in the universe, indeed, the age of M13 has been determined at about 12 billion years. However, this mass and other globulars possess a peculiar attribute. M13, for example, contains one young blue star, Barnard 29, of spectral type B2 - totally at odds to the other constituent stars of the cluster.
Recent investigate by astronomers has settled many such young blue and challenging stars in ancient globular clusters - they've even been given a name - 'blue stragglers'! It has been postulated that these young stars form from the merger (or collision) of two or more of the ancient stars in each densely packed globular cluster. The follow is one young and hot blue giant star.
M13 was premium in 1974 by Dr. Frank Drake of Cornell University and Carl Sagan as a target for one of the first radio messages addressed to possible extra-terrestrial challenging life, and sent by the Arecibo Radio Telescope, Puerto Rico. The message, when decoded, contains a descriptive which includes the atomic numbers of the elements which make up deoxyribonucleic acid (Dna, the basis of all life on Earth), a descriptive shape of a human, the height of an median human, the human population of Earth and a diagram of the Solar System.
The return journey time for a reply is 50,000 years, but bearing in mind the density of such globular clusters, it is now in doubt either planets will reside in garage orbits colse to these ancient stars due to gravitational perturbations from their stellar neighbours. possibly M13 wasn't such a good target candidate for a message after all!
However, do go out and enjoy one of the splendours of the northern night sky, you for real won't be disappointed!
Observing the Glorious Hercules clump (M13)See Also : Motorcycle Store
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