[Aquarius]
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Aquarius
Source of All Rivers


according to the Arabs, is a constellation associated with the rainy season of the ancient middle east. Persian, Syrian and Turkish languages call it the Water Bucket. The Egyptians associated these stars with Khnum, their god of water, who caused the Nile to overflow when he dipped his water bucket into the river. Remember the importance of the overflowing Nile as it brought nutrients and fertility to the crops. The Egyptian heiroglyph for water is the same as the sign used by astrologers for Aquarius, a pair of wavy lines suggesting the surface of a river. At times the constellation has been depicted as an ass carrying two water lugs on its back.

The Greeks held to this same idea, but named the constellation for Ganymede, the Trojan boy carried off to Mount Olympus to serve as cup-bearer to the gods.

Aquarius is the first sign of the zodiac in India, where its patron saint is Varuna. This ancient god was originally the all-powerful lord of all the heavens and creator of the stars. But later he was looked on as just god of the water who looked down on the Earth through the thousand eyes of the stars. From his throat issued the seven streams of heaven. Varuna patrols his realm on a fabulous steed, half crocodile and half bird. So he is quite able to patrol both the air and the sea.

The stars of Aquarius lie between those of Pisces and Capricornus along the ecliptic. To the north is the Great Square of Pegasus, and to the south is the first-magnitude star Fomalhaut. Thus it is an important star group, although it has only a few important stars. Its alpha star, Sadalmelik, is only at magnitude 3.2, and there are only about 20 other stars brighter than fifth magnitude. However, some of these stars form asterisms, star patterns such as the Water Jar, a trefoil (resembling the Mercedes-Benz symbol) of Pi, Gamma, and Eta-Aquarii surrounding Zeta. This Y-shaped group lies to the east of Sadalmelik. Zeta-Aquarii is one of a number of interesting double stars. It is a beautiful pair of fourth-magnitude stars separated by about 3 arcseconds. The colors of the pair are given as pale green and pale yellow. Another star of note is R-Aquarii, a Mira-type variable star which, over the space of a year, changes from a dim magnitude 11 to a magnitude of six.

There are three Messier objects in Aquarius, including M2 and M72, both globular clusters. M2 is one of the better clusters and one which can be visible to a keen-eyed observer on a really dark night. In a small telescope it becomes a ball of faint stars of magnitude 13. M73 is a rather unusual object among those listed by Messier. It is only a small group of stars of similar magnitude that are possibly associated as a multiple-star system. It is also referred to as NGC 6994. First observed in October 1780, M73 was described by Messier as “three or four small stars which look like a nebula at first sight” and contain “a little nebulosity.” Yet no photograph of M73 has ever revealed nebulosity around these stars. The four stars form the shape of a Y, and their magnitudes range from 10.5 to 12.0.

Two planetary nebulae take preeminence in a long list of other deep-sky objects in Aquarius. The Saturn Nebula, when seen through a telescope, is a small blue-green dot that Lord Rosse thought looked like a ringed planet.

The other, the Helix Nebula, NGC 7293, is the closest planetary nebula to us and occupies an area about half the diameter of the full Moon. This marvelous deep-sky object can be seen in binoculars from dark skies. A cloud of gas and dust ejected from a central star, it resembles a dim smoke ring. Planetary nebulae were named by Sir William Herschel in 1785 because in telescope views they may resemble planets. About a thousand of these shells of stars in their final stages of evolution from giants to dwarfs are known. The central stars are usually blue in color with temperatures up to 400,000K.

The planet Neptune was discovered among the stars of Aquarius 154 years ago, in 1846, after its presence had been predicted and calculated from irregularities in the orbit of Uranus. Aquarius is also the radiant location for several meteor showers, including the Eta Aquarids of May, the North Delta Aquarids which peak on July 29, the South Delta Aquarids which peak on August 13, and the lesser Iota Aquarids, also of August.


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