It’s October already. Nights are getting longer. You don’t need to wait so long after supper to get out to star-gaze. When it’s dark enough and the skies are clear, you must go outside to see the stars.
This month we are featuring the constellation Hercules, well-placed above the horizon in the western sky. There are many interesting things about this Constellation, but we’ll mention only a few highlights.
Hercules is one of the strong men in Greek and Roman myth. Hercules was fathered by Zeus, the chief god and the mortal woman was Alcmene. Naturally, Zeus’ wife became jealous, but that’s another story.
Hercules became very strong and was the main character in many Greek myths, “including the expedition of the Argonauts, the deliverance of Prometheus from his bondage high atop a crag in the Caucasus, and the Twelve Labors.” (R. Burman, Celestial Handbook, p. 962.)
One of the “Twelve Labors” was Hercules killing the troublesome Nemean Lion by stuffing his arm down the Lion’s throat. Later, Hercules removed the lion’s tough skin and wore it for his armor.
Another Labor was killing the ugly Hydra, a serpent with nine poisonous heads. One of the heads was immortal, which Hercules had to bury separately.
How could any culture develop such disturbing myths? However, Hercules was honored for his courage and strength by placing him in the sky as a Constellation.
Hercules’ brightest star is named Ras Algethi, a derivation of Ras Jathiyy, Arabic for “Head of the Kneeler.” It is also known as “alpha Herculis,” shown by the Greek letter alpha “a” on starmaps.
“Alpha Hercules” is the brightest star in the constellation. Ras Algethi is about 430 light-years from us and is a red-super-giant. Its diameter is an incredible 350,000,000 miles, roughly equivalent to Betelguese in Orion. It has the astronomical designation of M 5 II (M meaning that it is a very red, cool star; 5 indicating that it is mid-range of M type stars; and II indicating it is really huge.
Hercules is best known as having a star-keystone to designate his body. A Hareculis can be found by locating the keystone shape and starting with the upper left star of the keystone.
Follow the two stars to the left and the second star is Ras Algethi. Binoculars will help.
You can get a free map of the night sky of October by going to www.skymaps.com
The Hercules constellation is known for its massive and beautiful cluster of stars called M 13, the 13th object which is not a comet, discovered by astronomer Messier, thus abbreviated M 13.
According to Mary Proctor, astronomer, “it is the finest of all the clusters in the northern skies.
Try to find this sparkling object. Again, start with the Hercules keystone. Locate its lower right-hand star. Then go slowly to the lower left-hand star. About one-fourth of the way to that star, you should see a nice blurry object. It has roughly one-half million stars. Its light has traveled for 22,000 years to get to us.
This M 13 should be known as “that wonderful, magnificent, amazing cluster of many hundreds of thousands of stars.” Enjoy!