Aquarius, or the "Water Bearer," is a constellation in the southern hemisphere. It is one of the 12 constellations of the Zodiac family, which lie on the Sun's apparent path in the sky. Its name means "water bearer" or "cup bearer" in Latin. Aquarius is one of the oldest recognized constellations in the sky. In Greek mythology, it is identified with Ganymede, a handsome young man Zeus fell in love with and, taking the form of an eagle (Aquila
), carried off to Olympus to serve as cup-bearer to the gods.
The stars in the Aquarius constellation can be interpreted as resembling the figure of a man holding a bucket with a pouring stream of water. The constellation Crater
is often referred to as his cup. In Babylonian astronomy books, Aquarius is called "GU.LA" or "The Great One" and identified with the god Ea, the ruler of the southern quarter of the Sun's path, the "Way of Ea." In the Hindu zodiac, Aquarius is called "kumbha," which also means "water-pitcher."
The Aquarius constellation occupies an area of 980 square degrees and contains five stars with known planets. It can be seen at latitudes between +65° and -90° and is best visible at 9 p.m. during the month of October. The constellation lies in the region sometimes referred to as the Sea, or the Water, an area occupied by many water-related constellations, including Cetus
(the Whale), Delphinus
(the Dolphin), Eridanus
(the Great River) and Pisces
(the Fish). In sidereal astrology, the Sun passes through Aquarius from mid-February to mid-March. In popular (tropical) astrology, the Sun is considered to pass through Aquarius from January 20 to February 18.
The brightest star in the Aquarius constellation is 
, beta Aquarii, also known by its traditional name Sadalsuud. The name derives from the Arabic phrase "sa’d al-suud," meaning "luck of lucks." Beta Aquarii has a magnitude of 2.9 and lies 610 light-years from Earth. It is classified as one of the rare yellow supergiants.
The second brightest star in the constellation is 
, alpha Aquarii, or Sadalmelik, a gigantic star 760 light-years away from Earth with a diameter 60 times that of our Sun. Sadalmelik is also classified as a G-type (yellow) supergiant. Its name derives from the Arabic expression "sa’d al-malik," meaning "luck of the king." Alpha Aquarii is also known by the name Rucbah, which it shares with 
With an apparent magnitude of 3.27, 
delta Aquarii, is the third brightest star in the constellation. It is traditionally known as Skat, from the Arabic "as-saq," for "leg" or "shin," a name that sometimes also refers to 
beta Pegasi. Delta Aquarii is thought to be one of the stream stars in the Ursa Major Moving Group, also known as Collinder 285, a moving group of stars with a core 80 light-years away, that share common velocities and are believed to have a common origin.
Another notable star is 
gamma Aquarii, or Sadalachbia (Sadachbia), from the Arabic expression "sa’d al-axbiyah," meaning "luck of the homes." Gamma Aquarii has an apparent magnitude of 3.84 and is 158 light-years distant from Earth.
Zeta Aquarii is the central star in the "water jar" asterism, located about 103 light-years from Earth. It is a binary star composed of 
a yellow-white F-type main sequence dwarf, and 
a yellow-white F-type subgiant. The binary star is also known as Sadaltager, from the Arabic phrase "sa’d al-tajir," meaning "luck of the merchant."
R Aquarii, is another interesting star in the Aquarius constellation. It is a variable, a symbiotic star system consisting of a Mira-type variable red giant and a white dwarf. Because of its location in a dusty area of space, the star system appears reddened. The nebula surrounding it, known as Cederblad 211, has never been observed visually and is believed to be a remnant of a nova-like explosion.
The Aquarius constellation contains several notable deep sky objects. Messier 2 is a bright globular cluster that can be seen with the naked eye on a dark sky. Messier 72 is another globular cluster that only appears as a small hazy area when observed with a small telescope. Messier 73 is a small asterism that consists of four stars. NGC 7009, or the Saturn Nebula, is one of the brightest planetary nebulae, named after the planet Saturn because it is similar in shape. NGC 7293, or the Helix Nebula, is the closest planetary nebula to Earth, only 400 light-years away.
Aquarius is home to several planetary systems. Gliese 876 is the first dwarf star with a planetary system ever discovered. It contains three planets, including a terrestrial one with a mass 6-8 times that of the Earth. Gliese 849 b is an extrasolar planet, the first long-period Jupiter-like planet ever seen orbiting a red dwarf. 91 Aquarii b is an extrasolar planet orbiting an orange giant.
Aquarius belongs to the Zodiac family of constellations, along with Leo
Constellations directly bordering Aquarius are Pisces
, Piscis Austrinus