{{Dablink|This article is about the astrological sign. For the song, see Aquarius/Let the Sunshine In. For other uses, see Aquarius.}}
{{otheruses|Aquarius (disambiguation)}}
Aquarius is a
constellationIn modern astronomy, a constellation is an area of the celestial sphere, defined by exact boundaries.The term "constellation" can also be used loosely to refer to just the more prominent visible stars that seem to form a pattern in that area.-Definitions:...
of the
zodiacIn astronomy, the zodiac is the ring of constellations that lines the ecliptic, which is the apparent path of the Sun across the sky over the course of the year. The Moon and planets also lie within the ecliptic, and so are also within the constellations of the zodiac. In astrology, the zodiac...
, situated between
CapricornusCapricornus is one of the constellations of the zodiac; it is often called Capricorn, especially when referring to the corresponding astrological sign. Its name is Latin for "horned male goat" or "goat horn", and it is commonly represented in the form of a sea-goat: a mythical creature that is half...
and
PiscesPisces is a constellation of the zodiac. Its name is the Latin plural for fish, and its symbol is . It lies between Aquarius to the west and Aries to the east.-Notable features:...
. Its name is
LatinLatin is an Italic language originally spoken in Latium and Ancient Rome. Through the Roman conquest, Latin spread throughout the Mediterranean and a large part of Europe...
for "
waterWater is an ubiquitous chemical substance that is composed of hydrogen and oxygen and is essential for all known forms of life.In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor or steam. Water covers 71%...
-bearer" or "
cup-bearer", and its symbol is
({{Unicode|Unicode ♒}}), a representation of water.
Aquarius is one of the oldest of the recognized constellations along the
zodiacIn astronomy, the zodiac is the ring of constellations that lines the ecliptic, which is the apparent path of the Sun across the sky over the course of the year. The Moon and planets also lie within the ecliptic, and so are also within the constellations of the zodiac. In astrology, the zodiac...
(the
sunThe Sun is the star at the center of the Solar System. The Earth and other matter orbit the Sun, which by itself accounts for about 99.86% of the Solar System's mass....
's apparent path). It is found in a region often called the
SeaThe Sea or the Water is an area of the sky in which many water-related, and few land-related, constellations occur.Most of these constellations are named by Ptolemy:* Aquarius the Water-bearer* Capricornus the Sea-goat* Cetus the Whale...
due to its profusion of constellations with watery associations such as
CetusCetus is a constellation in the northern sky. Its name refers to Cetus, a sea monster in Greek mythology, although it is often called 'the whale' today...
the
whaleWhale is the common name for marine mammals of the order Cetacea. The term whale is sometimes used to refer to all cetaceans, but in more common English usage it generally excludes the members of the Delphinoidea superfamily, such as dolphins and porpoises...
,
PiscesPisces is a constellation of the zodiac. Its name is the Latin plural for fish, and its symbol is . It lies between Aquarius to the west and Aries to the east.-Notable features:...
the
fishA fish is any aquatic vertebrate animal that is typically ectothermic , covered with scales, and equipped with two sets of paired fins and several unpaired fins...
and
EridanusEridanus is a constellation. It is represented as a river; its name is the Ancient Greek name for the Po River. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains one of the 88 modern constellations. It is the sixth largest of the modern...
the
riverA river is a natural watercourse, usually freshwater, flowing toward an ocean, a lake, a sea or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water...
.
Planetary systems
- Gliese 876
Gliese 876 is a red dwarf star approximately 15 light-years away from Earth in the constellation of Aquarius . As of 2008, it has been confirmed that three extrasolar planets orbit the star...
is the first planetary systemA planetary system consists of the various non-stellar objects orbiting a star such as planets, dwarf planets, moons, asteroids, meteoroids, comets, and cosmic dust...
found around a red dwarfAccording to the Hertzsprung-Russell diagram, a red dwarf star is a small and relatively cool star, of the main sequence, either late K or M spectral type...
star. The planetary system has three planets, including one terrestrial planetA terrestrial planet, telluric planet, rocky planet or inner planet is a planet that is primarily composed of silicate rocks. Within the solar system, the terrestrial planets are the closest planets to the Sun...
6-8 times the mass of Earth.
- 91 Aquarii b
91 Aquarii b, also known as Psi1 Aquarii b, is an extrasolar planet orbiting in the 91 Aquarii system approximately 148 light-years away in the constellation of Aquarius. 91 Aquarii b is a hot Jupiter with mass nearly three times that of Jupiter. It orbits at the average distance of...
is a planet found around the orange giant star. The mass is 2.9 times JupiterJupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with a mass slightly less than one-thousandth that of the Sun but is two and a half times the mass of all of the other planets in our Solar System combined. Jupiter is classified as a gas...
and the semimajor axis of 0.3 AU.
- Gliese 849 b
Gliese 849 b is an extrasolar planet approximately 29 light years away in the constellation of Aquarius. This is the first long-period Jupiter-like planet discovered around a red dwarf star, announced in August 2006 by the California and Carnegie Planet Search team using the radial velocity technique...
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.
Deep sky objects
There are three deep sky objects that are on the
Messier catalogThe Messier objects are a set of astronomical objects first listed by French astronomer Charles Messier in his "Catalogue des Nébuleuses et des Amas d'Étoiles" included in the Connaissance des Temps for 1774...
: the globular clusters
Messier 2Messier 2 or M2 is a globular cluster in the constellation Aquarius, five degrees north of the star Beta Aquarii...
,
Messier 72Messier 72 is a globular cluster in the Aquarius constellation discovered by Pierre Méchain in August 29 1780. Charles Messier looked for it on the following October 4 and 5, and included it in his catalog. Both decided that it was a faint nebula not a cluster as is now believed...
, and the open cluster
Messier 73Messier 73 is an asterism of four stars in the constellation of Aquarius. An asterism is comprised of physically unconnected stars that appear close to each other in the sky as seen from Earth...
. Two well-known
planetary nebulaA planetary nebula is an emission nebula consisting of an expanding glowing shell of ionized gas and plasma ejected during the asymptotic giant branch phase of certain types of stars late in their life...
e are located in Aquarius: the
Saturn NebulaThe Saturn Nebula is a planetary nebula in the Aquarius constellation. It was discovered by William Herschel on September 7, 1782 using a telescope of his own design in the garden at his home in Datchet England and was one of his earliest discoveries in his sky survey...
(NGC 7009), to the southwest of
η AquariiEta Aquarii is a star in the constellation Aquarius. It has the occasional proper name Hydria, from the Greek ‘υδρια hudria "water jar".Eta Aquarii is a blue-white B-type subgiant with an apparent magnitude of +4.04...
; and the famous
Helix NebulaThe Helix Nebula, also known as The Helix or NGC 7293, is a large planetary nebula located in the constellation of Aquarius. Discovered by Karl Ludwig Harding, probably before 1824, this object is one of the closest to the Earth of all the bright planetary nebulae. The estimated distance is about...
(NGC 7293), southwest of δ Aquarii.
Conventional
The stars of Aquarius can be seen as resembling the figure of a man, and, when fainter
naked eyeThe naked eye is a figure of speech referring to human visual perception that is unaided by enhancing equipment, such as a telescope or microscope. Vision corrected to normal acuity using corrective lenses is considered "naked"...
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 AustrinusPiscis Austrinus is a constellation in the southern celestial hemisphere. The name is Latin for "the southern fish" in contrast with the larger constellation Pisces, which represents a pair of fishes. Prior to the 20th century, it was also known as Piscis Notius...
.
Alternative
{{SectOR|date=November 2008}}
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
quadrangleIn geometry, a quadrilateral is a polygon with four 'sides' or edges and four vertices or corners. Sometimes, the term quadrangle is used, for analogy with triangle, and sometimes tetragon for consistency with pentagon , hexagon and so on. The word quadrilateral is made of the words quad and...
of
α Aqr| name = α Aquarii}}Alpha Aquarii , which also has the traditional name Sadalmelik, is the second-brightest star in the constellation Aquarius...
,
γ AqrGamma Aquarii is a star in the constellation Aquarius. It has the traditional name Sadachbia, from an Arabic expression سعد الأخبية sa‘d al-’axbiyah "luck of the homes "....
,
η AqrEta Aquarii is a star in the constellation Aquarius. It has the occasional proper name Hydria, from the Greek ‘υδρια hudria "water jar".Eta Aquarii is a blue-white B-type subgiant with an apparent magnitude of +4.04...
, and
π AqrPi Aquarii or Seat is a star in the constellation Aquarius. The name Seat is shared with Delta Aquarii, where it has long been misspelled Skat. It may be from the Arabic word ši'at "a wish"....
: α Aqr being of the third magnitude. Star
ζ AqrZeta Aquarii is a binary star, the central star in the “water jar” asterism in the constellation Aquarius...
, lodged within the quadrangle, represents an eye.
The water bearer's torso is formed by the stars α Aqr and
β Aqris the brightest star in the constellation Aquarius. It has the traditional name Sadalsuud, from an Arabic expression سعد السعود sa‘d al-su‘ūd "luck of lucks"....
, with β Aqr being of the third magnitude.
The water bearer's left leg is formed by the stars β Aqr and
ι AqrIota Aquarii is a star in the constellation Aquarius.Iota Aquarii is a blue-white B-type subgiant with an apparent magnitude of +4.29. It is approximately 173 light years from Earth.-References:* *...
, whereas his right leg is formed by the stars β Aqr,
ν AqrNu Aquarii is a star in the constellation Aquarius. It shares the traditional name Albulaan with μ Aquarii. The name derives from an Arabic term al-bula
cān meaning "the two swallowers"....
,
μ AqrMu Aquarii is a binary star in the constellation Aquarius. It is approximately 155 light years from Earth. It shares the traditional name Albulaan with ν Aquarii. The name derives from an Arabic term al-bulacān meaning "the two swallowers".Mu Aquarii is a spectroscopic binary which...
, and
ε AqrEpsilon Aquarii is a star in the constellation Aquarius. It has the an obscure traditional name, Albali, from the Arabic البالع albāli‘ "the swallower". It is known as 女宿一 in Chinese.Albali belongs to the spectral class A0 and has an apparent magnitude of +3.8...
, with these last two stars representing a foot.
The water bearer's arm is formed by the stars α Aqr,
θ AqrTheta Aquarii is a star in the constellation Aquarius. It has the traditional name Ancha, Latin for "the haunch"....
, and
λ AqrLambda Aquarii is a star in the constellation Aquarius. It has the obscure traditional names Hydor and Ekkhysis, from the ancient Greek ‘υδωρ "water" and εκχυσις "outpouring"....
, 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 AqrPhi Aquarii is a star in the constellation Aquarius.Phi Aquarii is a M-type red giant with an apparent magnitude of +4.22. It is approximately 222 light years from Earth.-References:* *...
, λ Aqr,
τ AqrThe Bayer designation Tau Aquarii is shared by two star systems, in the constellation Aquarius:* τ1 Aquarii* τ2 AquariiThey are separated by 0.65° on the sky....
, and
δ AqrDelta Aquarii is the third-brightest star in the constellation Aquarius. It has the traditional name Skat, which can also refer to Beta Pegasi....
. 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 Aqr98 Aquarii is a star in the constellation Aquarius.98 Aquarii is an orange K-type giant with an apparent magnitude of +3.96. It is approximately 162 light years from Earth....
,
99 Aqr99 Aquarii or b 2 Aquarii is a star in the constellation Aquarius. Its apparent magnitude is 4.38.-References:* *...
, and
101 Aqr101 Aquarii or b3 Aquarii is a binary star in the constellation of Aquarius.-References:* *...
. The streamline on the right is formed by the stars ψ¹ Aqr,
88 Aqr88 Aquarii or c
2 Aquarii is a star in the constellation Aquarius.88 Aquarii is an orange K-type giant with an apparent magnitude of +3.68. It is approximately 234 light years from Earth.-Location:...
,
89 Aqr89 Aquarii is a star in the constellation Aquarius. Its apparent magnitude is 4.71.-References:* *...
, and
86 Aqr86 Aquarii or c 1 Aquarii is a star in the constellation Aquarius. Its apparent magnitude is 4.48. It is approximately 116 ly from Earth.-References:* *...
.
Mythology
Aquarius is named {{lang|sux-Latn|GU.LA}} "The Great One" in the
Babylonian star cataloguesOld Babylonian astronomy inherited systems of star catalogues from Sumerian sources.The Babylonians grouped the stars in companies of seven. References are made to the seven Tikši, the seven Lumaši, and the seven Maši....
and represents the god Ea himself. It contained the
winter solsticeWinter solstice may refer to:* Winter solstice, astronomical event* Winter Solstice , former band* Winter Solstice: North , seasonal songs* Winter Solstice , 2005 American film...
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 AustrinusPiscis Austrinus is a constellation in the southern celestial hemisphere. The name is Latin for "the southern fish" in contrast with the larger constellation Pisces, which represents a pair of fishes. Prior to the 20th century, it was also known as Piscis Notius...
. The name in the Hindu zodiac is likewise
kumbha "water-pitcher", showing that the zodiac reached India via Greek intermediaries.
Aquarius is sometimes identified with
GanymedeIn Greek mythology, Ganymede, or Ganymedes is a divine hero whose homeland was Troy. He was a Trojan prince, son of the eponymous Tros of Dardania, and of Callirrhoe, and brother of Ilus and Assaracus...
, a beautiful youth in
Greek mythologyGreek mythology is the body of myths and legends belonging to the ancient Greeks concerning their gods and heroes, the nature of the world, and the origins and significance of their own cult and ritual practices. They were a part of religion in ancient Greece...
with whom
ZeusIn Greek mythology, Zeus is the king of the gods, the ruler of Mount Olympus and the god of the sky and thunder. His symbols are the thunderbolt, eagle, bull, and oak. In addition to his Indo-European inheritance, the classical "cloud-gatherer" also derives certain iconographic traits from the...
fell in love and, in the disguise of an eagle (represented by the constellation
AquilaAquila is a constellation. Its name is Latin for 'eagle' and it is commonly represented as such. It lies roughly at the celestial equator. The alpha star, Altair, is a vertex of the Summer Triangle asterism.-History:...
) carried off to Olympus to be cup-bearer to the gods. The constellation of
CraterCrater is a constellation. Its name is Latin for cup, and in Greek mythology it is identified with the cup of the god Apollo. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations...
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
EridanusEridanus is a constellation. It is represented as a river; its name is the Ancient Greek name for the Po River. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains one of the 88 modern constellations. It is the sixth largest of the modern...
the river is sometimes identified as a river being poured by Aquarius.
Aquarius may also, together with the constellation
PegasusPegasus is a constellation in the northern sky, named after the winged horse Pegasus in Greek mythology. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations.-Stars:...
, be part of the origin of the myth of the
Mares of DiomedesThe Mares of Diomedes, also called the Mares of Thrace, were four man-eating horses in Greek mythology. Magnificent, wild, and uncontrollable, they belonged to the giant Diomedes , king of Thrace, a son of Ares and Cyrene who lived on the shores of the Black Sea...
, which forms one of The Twelve Labours of
HeraclesIn Greek mythology, Heracles or Herakles , Alcides or Alcaeus , was a divine hero, the son of Zeus and Alcmene, foster son of Amphitryon and great-grandson of Perseus...
. Its association with pouring out rivers, and the nearby constellation of
CapricornusCapricornus is one of the constellations of the zodiac; it is often called Capricorn, especially when referring to the corresponding astrological sign. Its name is Latin for "horned male goat" or "goat horn", and it is commonly represented in the form of a sea-goat: a mythical creature that is half...
, may be the source of the myth of the Augean stable, which forms another of the labours.
Astrology
{{main|Aquarius (astrology)}}
{{As of|2002}}, the Sun appears in the constellation Aquarius from February 16 to March 11. In
tropical astrologyTropical astrology is a type of astrology based on a zodiac whose points of reference are the tropics. The word tropic comes from the Greek for "turning point," and originally meant the point at which the sun at sunrise and sunset appears to turn, and to move north in the northern hemisphere and...
, the Sun is considered to be in the sign
Aquarius{{Dablink|This article is about the astrological sign. For the song, see Aquarius/Let the Sunshine In. For other uses, see Aquarius.}}{{Dablink|This article is about the astrological sign. For the song, see Aquarius/Let the Sunshine In...
from January 20 to February 18, and in
sidereal astrologySidereal astrology is the system of astrology used by some Western and all Jyotish astrologers who base their interpretation around the use of the sidereal zodiac. Its primary feature is that the signs of the zodiac align to the sky constellations of the same name. The signs therefore run between...
, from February 15 to March 14.
External links
{{Commons|Aquarius}}
{{Zodiac}}
{{navconstel}}
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