Sagittarius
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Sagittarius Points the Way Toward the Core of the Milky Way

+ Von Del Chamberlain +

Copy for August 24, 1997

Of all the mythological creatures, none is more imaginative nor interesting than the centaur, half man and half horse. There are two of them in the starry firmament, the constellation Centaurus too far south for us to completely see, but the other is in position now to get a look at in on clear evenings. Sagittarius, the great archer-centaur rides above the southern horizon as darkness comes.

Association of these stars with an archer apparently came out of Mesopotamia, with the centaur added to the figure by the Greeks. The constellation is said to have represented Chiron, legendary son of Cronus (Roman Saturn). Chiron was credited as the source of wisdom, medicine, and music and was also considered to be a great marksman. He was gentle and kind and taught people the uses of plants and herbs for medicines. As the quintessential educator, it was said that his pupils included Achilles, Apollo, Hercules and Jason. At one point in his life on earth he changed himself into part horse to escape his jealous wife, Rhea. Chiron inherited immortality from his father, but was accidentally wounded by one of Hercules' arrows that had been dipped in the poisonous blood of Hydra. Unable to die, he would have suffered eternal pain, had not Zeus released him from immortality, then placed him among the stars. Forever he would be pictured with human body to the waist plus four legs and stout hind parts of a horse. Thus he would be swift, yet endowed with great intelligence and agility of human arms and hands. Now jeweled with the stars of Sagittarius he is imagined holding a drawn bow with the arrow aimed straight at the heart of Scorpius, the scorpion. The ancient poet, Ovid, wrote:

Midst golden stars he stands refulgent now
And thrusts the Scorpion with his bended bow.

Another version of the story indicates that it was the wise Chiron himself who invented the constellations so that people could remember legendary heroes, foretell seasons and measure time. He made one figure in his own likeness, the horse-man-archer, with special purpose of guiding his student Jason and the other Argonauts to find the Golden Fleece.

Sagittarius is one of the most important regions of the sky to be known by those wishing to understand the cosmos. The Sun lies against those stars when it reaches the winter solstice, and the center of the Milky Way Galaxy is in that direction. Although Sagittarius does not have any of the brightest stars, it is decorated with some of the most beautiful and interesting deep-sky objects. Many great gaseous clouds called nebulae and both small and gigantic clusters of stars are there, making it the prime part of the sky to browse with binoculars or telescope. If you watch the region long enough you can see planets pass through, find young and old stars, and study all the processes of creation still going on in our galaxy. Many science fiction writers have imagined what might go on out there at the very core of our galaxy.

Getting out of lights on a dark and clear night, it is amazing what can be seen with just your eyes, and your attention will always be drawn along the Milky Way toward the southern horizon where you find Sagittarius, the brightest part of that "River of Light." From a country place you will see considerable structure to the Milky Way: bright clouds of star light; dark pathways and delicate tentacles of dust blocking the light of stars beyond. Some of the nebulae and star clusters are even visible to the naked eye as bright spots. They are beautiful in a pair of binoculars and spectacular in a telescope. What a mental feast we have within the boundaries of Sagittarius.

When you go out to look around our galaxy on these August evenings, Sagittarius will be low in the south, just east of Scorpius. Recalling that Scorpius resembles the letter "J," a fishhook, or a scorpion, Sagittarius is the bunch of stars to the left. Although its classical form is the centaur-archer, it is easiest to recognize its most prominent stars as a teakettle. The spout of the kettle is formed by a small triangle with one star at the bottom and a pair above. The lid is composed by another triangle of stars attached to the left upper lip of the spout. The handle of the teapot is four stars left of the bottom of the lid. The handle combined with the top of the lid and yet another star, higher and slightly left, forms a small perfect dipper, referred to as the "Milk Dipper of Sagittarius."

With Sagittarius we have arrived at the edge of the ancient "ocean of heaven," the watery constellations, three of which we will explore over the next three months to conclude our navigation round the zodiac. You can find Sagittarius easiest by getting out of the city on a moon-less clear night to follow the Milky Way currently dividing our evening sky. Pick it up in the north, notice that a dark rift starts overhead and separates it into two bright paths toward the southern horizon where you come to the teakettle formed by stars. Looking into this region you are focusing toward the heart of the great Milky Way Galaxy, the city of several-hundred-billion stars composing the cosmic star-hive we live in. What great and wondrous discoveries have come from human minds, looking around, engaged in exploration!

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