Aquarius is a constellation known as the Water Bearer. It sits in the southern sky between the constellations Pisces and Capricornus. It is best viewed around September through November. Aquarius was one of the 48 constellations defined by the ancient Greek mathematician Ptolemy. Today, it is one of 88 constellations recognized by the International Astronomical Union, the leading authority in the naming of heavenly objects. Aquarius is also one of the 12 signs of the zodiac used in astrology (see Aquarius [astrology] ).
Aquarius is said to represent a man holding a water pitcher. It can be drawn in several ways. In one helpful approach, the constellation includes about 16 main stars. Nine of the stars form a stick figure of a person. His “arm” holds five stars suggesting a water pitcher. Two stars below the “spout” of the pitcher represent water spilling out.
Aquarius contains the Helix Nebula, one of the closest planetary nebula to Earth. A planetary nebula is a cloud of dust and gas thrown out by a star, similar to the sun in size, as it dies. The Helix Nebula lies about 700 light-years away. A light-year is the distance light travels in a vacuum in a year, about 5.88 trillion miles (9.46 trillion kilometers).
