Aquarius (constellation)
- Delta Aquariiden
- Eta Aquariiden
- Iota Aquariiden
- Pegasus
- Dolphin
- Eagle
- Capricorn
- Southern fish
- Sculptor
- Whale
- Pisces
The Aquarius ( Aquarius Latin, ancient Egyptian giant; astronomical sign ♒ ) is a constellation of the ecliptic.
Description
Aquarius is an extensive but little conspicuous constellation south of Pegasus. Only two of its stars are brighter than the third magnitude. The sun keeps from 16 February to 12 March of each year in Aquarius.
The Radiant alljährlicher two shooting stars swarms located in this constellation: the May Aquariiden and the July Aquariiden.
History
Although the Aquarius is not a conspicuous constellation, he is considered one of the oldest known constellations. For the ancients, he must have had a great importance as a calendar characters. When the sun wandered into Aquarius, this marked the time of the rainy season. Hence the name probably derives. Several constellations in the area, like the fish, the whale, the southern fish and the dolphin also have a connection to the water.
In the 1960s, the constellation became very popular because supposedly the astrological " Age of Aquarius " had dawned ( sung in the song " Aquarius " from the musical Hair). Because the vernal equinox is due to the precession since the middle of last century about to switch from the sign of Pisces into Aquarius. In fact, there are no standard definitions for astrological age. That of Aquarius can begin between 1990 and 2150 accordingly (depending on definition).
The zodiac sign of Aquarius goes back to this constellation.
Mythology
For the mythological origin of the name, there are several interpretations. One is in the Aquarius Deucalion is supposed to represent, who survived the Flood and was the progenitor of the people. When Zeus wanted to wipe out the sinful mankind, Deucalion built a boat, he and his wife Pyrrha nine days and nights with the exaggerated on the water, until they landed on Mount Parnassus. Following an oracle, the two threw stones behind them, from which emerged a new man.
Other interpretations according to it should the Aquarius to Cecrops I, the founder of Athens, or Ganymede, Zeus ' cupbearer act.
Celestial objects
See also List of stars in the constellation Aquarius
Stars
Beta Aquarii is characterized by an apparent brightness of 2.90m the brightest star in Aquarius. He is a supergiant of spectral type G0 Ib in about 610 light years away. The name Sadalsuud is of Arabic origin and means something like " the happiness of happiness ".
The second brightest star, Alpha Aquarii ( Sadalmelik, Arabic " the happiness of the King"), is a 760 light-years distant supergiant of spectral type G2 Ib. He holds 80 times the diameter and the 6,000 times brighter than our sun.
Gamma Aquarii ( Sadachbia, Arabic " the luck of the tents "), is 158 light years away.
Delta Aquarii is 160 light years distant star of spectral type A3 V. The origin of its name Skat is mostly "leg" called. It could have but originally means " wish".
Double stars
ζ Aqr is a binary star system in 105 light years away. This circling two roughly equal star around a common center of gravity, for which they need about 800 years. The system can be resolved already in a small telescope in two bright white, about the same bright star.
Variable Stars
R Aquarii is a variable star of type Mira at 1,000 light- years away. The star changes over a period of 387 days, its brightness, with periodic fluctuations occur at a rate of 24 years. At the maximum, the star is 5.8 m bright and can barely be seen with the naked eye. At a minimum, it only reaches a brightness of 12.4 m. To begin finding him you need a larger telescope.
Messier and NGC objects
In Aquarius, there are three objects, which started the French astronomer and comet hunter Charles Messier in his catalog of nebulous objects ( Messier catalog).
M2 is a globular cluster about 50,000 light- years away. Already in binoculars it can be identified as misty spot. To resolve it into individual stars at the edge, however, you need a telescope.
M72 is a globular cluster about 60,000 light years away. He is the faintest globular clusters in the Messier catalog and can be resolved only in large telescopes.
M73 is not a real star clusters, but a group of four stars at a distance of 2,000 light- years away.
In about 3000 light years away is the planetary nebula NGC 7009, which is also called Saturn Nebula. With its elliptical shape, it is somewhat reminiscent of the ringed planet Saturn, if you watched this in a telescope at low magnification.
In the southern part you will find the Helix nebula. This is a planetary nebula in 500 light years away. With a diameter of 13 arc minutes and a brightness of 7m it is the largest and brightest planetary nebulae in the night sky. In a dark night, you can perceive it in binoculars as a round, misty spot. In order to identify structures, however, you need a telescope.