Aquarius (constellation)

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Aquarius

Constellation
List of stars in Aquarius
Abbreviation	Aqr
Genitive	Aquarii
Pronunciation	/əˈkwɛəriəs/, genitive /əˈkwɛəriaɪ/
Symbolism	the Water-bearer
Right ascension	23
Declination	−15
Area	980 sq. deg. (10th)
Main stars	10, 22
Bayer/Flamsteed stars	97
Stars with known planets	5
Bright stars	2
Nearby stars	4
Brightest star	β Aqr (Sadalsuud) (2.9m)
Nearest star	EZ Aqr (11.3 ly)
Messier objects	3
Meteor showers	March Aquariids Eta Aquariids Delta Aquariids Iota Aquariids
Bordering constellations	Pisces Pegasus Equuleus Delphinus Aquila Capricornus Piscis Austrinus Sculptor Cetus
Visible at latitudes between +65° and −90°. Best visible at 21:00 (9 p.m.) during the month of October.

Aquarius is a constellation of the zodiac, situated between Capricornus and Pisces. Its name is Latin for water-bearer or cup-bearer, and its symbol is (Unicode ♒), a representation of water.

Aquarius is one of the oldest of the recognized constellations along the zodiac (the sun's apparent path). It is found in a region often called the Sea due to its profusion of constellations with watery associations such as Cetus the whale, Pisces the fish and Eridanus the river.

[edit] Notable features

See also: List of stars in Aquarius

[edit] Planetary systems

• Gliese 876 is the first planetary system found around a red dwarf star. The planetary system has three planets, including one terrestrial planet 6-8 times the mass of Earth.
• 91 Aquarii b is a planet found around the orange giant star. The mass is 2.9 times Jupiter and the semimajor axis of 0.3 AU.
• Gliese 849 b is the first long-period Jupiter-like planet found around the red dwarf star. The semimajor axis is 2.35 AU and has mass of 0.82 Jupiter.

[edit] Deep sky objects

There are three deep sky objects that are on the Messier catalog: the globular clusters Messier 2, Messier 72, and the open cluster Messier 73. Two well-known planetary nebulae are located in Aquarius: the Saturn Nebula (NGC 7009), to the southwest of η Aquarii; and the famous Helix Nebula (NGC 7293), southwest of δ Aquarii.

[edit] Visualizations

[edit] Conventional

Aquarius pours water from a jar into the mouth of the southern fish, as depicted in Urania's Mirror, a set of constellation cards published in London c.1825

The stars of Aquarius can be seen as resembling the figure of a man, and, when fainter naked eye stars are included, it can take on the image of a man with a bucket from which is pouring a stream of water. The water flows southwards into the mouth of the southern fish, Piscis Austrinus.

[edit] Alternative

This section may contain original research or unverified claims. Please improve the article by adding references. See the talk page for details. (November 2008)

Diagram of an alternate way to connect the stars of the constellation Aquarius. The water bearer is shown running while holding a vessel and spilling some water out of that vessel.

The stars of the constellation Aquarius can be connected in an alternative way, which graphically shows the water bearer running while holding a vessel from which water is spilling.

The water bearer's head is formed by the quadrangle of α Aqr, γ Aqr, η Aqr, and π Aqr: α Aqr being of the third magnitude. Star ζ Aqr, lodged within the quadrangle, represents an eye.

The water bearer's torso is formed by the stars α Aqr and β Aqr, with β Aqr being of the third magnitude.

The water bearer's left leg is formed by the stars β Aqr and ι Aqr, whereas his right leg is formed by the stars β Aqr, ν Aqr, μ Aqr, and ε Aqr, with these last two stars representing a foot.

The water bearer's arm is formed by the stars α Aqr, θ Aqr, and λ Aqr, with λ Aqr being the hand.

The water bearer is holding a vessel, perhaps a jar, which is formed by the stars ψ¹ Aqr, φ Aqr, λ Aqr, τ Aqr, and δ Aqr. The open top of the vessel consists of the triangle of stars ψ¹ Aqr, φ Aqr, and λ Aqr.

Water is being poured from the vessel in a pair of streamlines. The streamline on the left is formed by the stars ψ¹ Aqr, 98 Aqr, 99 Aqr, and 101 Aqr. The streamline on the right is formed by the stars ψ¹ Aqr, 88 Aqr, 89 Aqr, and 86 Aqr.

[edit] Mythology

Aquarius is named GU.LA "The Great One" in the Babylonian star catalogues and represents the god Ea himself. It contained the winter solstice in the Early Bronze Age. In Old Babylonian astronomy, Ea was the ruler of the southernmost quarter of the Sun's path, the "Way of Ea", corresponding to the period of 45 days on either side of winter solstice. In the Greek tradition, the constellation became represented as simply a single vase from which a stream poured down to Piscis Austrinus. The name in the Hindu zodiac is likewise kumbha "water-pitcher", showing that the zodiac reached India via Greek intermediaries.^[1]

Aquarius is sometimes identified with Ganymede, a beautiful youth in Greek mythology with whom Zeus fell in love and, in the disguise of an eagle (represented by the constellation Aquila) carried off to Olympus to be cup-bearer to the gods. The constellation of Crater is sometimes identified as his cup.

Aquarius has also been identified as the pourer of the waters that flooded the Earth in the ancient Greek version of the Great Flood myth. As such, the constellation Eridanus the river is sometimes identified as a river being poured by Aquarius.

Aquarius may also, together with the constellation Pegasus, be part of the origin of the myth of the Mares of Diomedes, which forms one of The Twelve Labours of Heracles. Its association with pouring out rivers, and the nearby constellation of Capricornus, may be the source of the myth of the Augean stable, which forms another of the labours.

[edit] Astrology

As of 2002^[update], the Sun appears in the constellation Aquarius from February 16 to March 11. In tropical astrology, the Sun is considered to be in the sign Aquarius from January 20 to February 18, and in sidereal astrology, from February 15 to March 14.

[edit] Notes

^{^}  a. The dates of Aquarius for tropical astrology are approximate, typically either from January 21 to February 19, or from January 20 to February 18, depending on the exact time the Sun enters the sign each year, which varies slightly from year to year within a small range.

[edit] References

• Ian Ridpath and Wil Tirion (2007). Stars and Planets Guide, Collins, London. ISBN 978-0007251209. Princeton University Press, Princeton. ISBN 978-0691135564.
• H. A. Rey, The Stars—A New Way To See Them. Enlarged World-Wide Edition. Houghton Mifflin, Boston, 1997. ISBN 0-395-24830-2.
• This article incorporates text from the Encyclopædia Britannica, Eleventh Edition, a publication now in the public domain.

[edit] External links

Wikimedia Commons has media related to: Aquarius

• The Deep Photographic Guide to the Constellations: Aquarius
• NightSkyInfo.com: Constellation Aquarius
• WIKISKY.ORG: Aquarius constellation
• Star Tales – Aquarius

Astronomy | Constellations of the Zodiac
Aries	Taurus	Gemini	Cancer	Leo	Virgo	Libra	Scorpius	Ophiuchus	Sagittarius	Capricornus	Aquarius	Pisces
Astrology | Signs of the Zodiac
Aries	Taurus	Gemini	Cancer	Leo	Virgo	Libra	Scorpio	Sagittarius	Capricorn	Aquarius	Pisces

Coordinates: 23^h 00^m 00^s, −15° 00′ 00″