Sagittarius (Sgr)
"The Archer"

---

---

Mythology: Sagittarius is a representative from a group of mythological creatures called Centaurs -- beings that are half man and half horse.  Where we would usually expect to see a horse's neck, we find the lower torso of a man "growing" out of the horse.  A Centaur also has the arms of a man, so all together the creature has six limbs.  Such an idea may find its conception in reality.  The horse was, at first, a difficult animal to domesticate, so when people first witnessed warriors and raiders coming at them riding horses, in the confusion and fear, the riders and horses may have appeared as one creature.  Similar stories are found even in North America: the inhabitants of Mexico could not distinguish rider from horse when Spain invaded America.
    In Classical Mythology and in constellations, there are two famous Centaurs:  the first is Chiron, depicted by the constellation Centaurus, and the second is Crotus, depicted by the constellation Sagittarius.
    Crotus was the son of Pan and Eupheme.  Eupheme, a nymph, was also responsible for the nine Muses, the daughters of Zeus and Mnemosyne.  Eupheme raised the nine Muses and Crotus together.  The Muses are often recognized as being a source of inspiration, particularly for creative endeavors.  Indeed, in Classical times, these Muses were the Goddesses of the Arts and Sciences:

        Calliope, Eurterpe, and Erato -- poetry.
        Clio -- history.
        Melpomene -- tragedy.
        Polyhymnia -- song, writing, and mathematics.
        Terpsichore -- dancing.
        Thalia -- comedy.
        Urania -- astronomy and astrology.

Do note that these nine Muses are not the same as the Seven Sisters depicted by the open star cluster Pleiades.
    Although he was a skilled hunter and archer, Crotus also enjoyed the arts, as we might expect since he was raised with the nine Muses.  Crotus' place in the stars as the constellation Sagittarius is said to come from the Muses who begged Zeus to honor their brother upon his death.  Another version claims it was Crotus himself who asked Zeus to be placed among the stars upon his death.
        Sagittarius, like Leo, seems to be a very old constellation, and seems to have references in many cultures.  For example, outside of Greek mythology, there is a depiction of Sagittarius that refers to the constellation being Nerigal -- the Mesopotamian God of War.

Other Interesting Sights:  Although Sagittarius is described as a Centaur, many people just look for the "teapot" in the night sky, to the East of the letter "J" of Scorpio.
    Sagittarius is also interesting because it lies in the direction of the center of our Milky Way Galaxy.  Our galaxy is shaped much like a fried egg, with the yolk acting as the nucleus of our galaxy, and the thin white part of the egg acting as the spiral arms.  Our Solar System lies about 2/3 of the way out from the nucleus.  So, when we look toward the constellation Sagittarius, we are looking toward the "yolk" from within the "white part" of the egg.
    Sagittarius is also full of interesting sights -- there are fifteen Messier objects that can be found in the direction of this constellation.  The four most interesting ones are the Trifid Nebula (M20), the Lagoon Nebula (M8), the Hourglass Nebula (MyCn 18), and the globular star cluster M22:

    The Trifid Nebula (M20) is a spectacular collection of colors.  These colors come from the many young stars that inhabit this nebula.  These young stars are very hot (and therefore blue), and, in addition, these energetic young stars strip electrons off atoms in the surrounding gas.  When these electrons recombine with the gas, more blue and violet light is given off.  Some colors of the nebula, particularly the reds, come from reflection of starlight off of dust in the nebula.

    The Lagoon Nebula (M8, NGC6523) can actually be seen with just your eyes on a clear night -- it is that large.  Also illuminated by the many stars within it, it is a stellar nursery; that is, it is still active with star birth.  Indeed, it is home to the young open cluster NGC6530, formed only several million years ago.  Within the Lagoon Nebula is the spectacular Hourglass Nebula.

    The Hourglass Nebula (MyCn 18) is a planetary nebula -- what results when small stars run out of nuclear fuel.  When a small star can no longer carry on nuclear fusion in its core, its gases puff away to form a planetary nebula.  What remains of the original star is its core -- a dense, Earth-sized object called a white dwarf.  Below is a spectacular Hubble Space Telescope image of the Hourglass Nebula -- note how the rings of gas are flowing away from the center, where the dying star resides.

    The globular cluster M22 contains approximately 500,000 stars and is located about 9,600 light years away.  The central nucleus of this cluster is roughly 50 light years across.