Stockton Astronomical Society
Valley Skies - October 1998 Issue
Constellations:
Aquarius the Water Bearer
Gen: Aquarii
Abb: Aqr
Dec: 03.1° to -25.22°
RA: 20h 36m to 23h 54m
The constellation of Aquarius is not one of the easy ones to make out, having very few bright stars or a shape that is easy to remember. Probably the best way to find it is by a small "Y" shaped asterism made up of 4th magnitude stars. The "Y" marks the water jar and is located at the northern edge of the constellation.
Aquarius was originally the 10th constellation of the Zodiac. Since then and due to the Earth's precession, it is now listed as the 11th or more often the 12th constellation. According to those who believe in astrology, the Earth comes under the influence of a different Zodiac sign every 2,150 years. At this time we are in the Age of Pisces. So don't get rid of your tie dyed clothes yet. Some time after the year 2000 we will move into the Mystical Age of Aquarius.
Aquarius is an ancient constellation that dwells in an area of the sky known as "the Sea". During the time of early Mesopotamia and many other early civilizations the sun would be in the area of "the Sea" at the time of heavy winter rains and flooding. Some of the other constellations in "the Sea" include Pisces the Fish, Capricornus the Sea Goat, Piscis Austrinus the Southern Fish and Delphinus the Dolphin.
To the Greeks several mythological entities have carried the jar of Aquarius. The three most common are, Ganymede, who served wine from his urn to the Gods on Mount Olympus; Deucalion, the hero of the Thessalian flood; and Cecrops, an ancient King of Athens.
Aquarius has had other names as well. To the Chinese it was part of a larger constellation called the "Turtle" and later it symbolized a Dark Warrior. The ancient Persians called it "one hundred dwellings in the sky". The Persians view is very interesting because, in this area of the sky modern astronomers have found one of the richest galaxy fields in the sky. These galaxies are all 12th magnitude or fainter but it makes me wonder what the Persians saw or thought about when they named this area.
Exploring in Aquarius
To start this months star hop look in the southern evening sky for the center of the "Y" that marks the "Water Jar" or "Urn". This is Zeta Aquarii. From here look for the line of brighter stars heading to the WSW and ending just above the top and center of Capricornus.
Note: The chart included here provides only a rough guide to the constellation. To follow the detailed description, refer to chart 17 in Tirion's Sky Atlas 2000 (or equivalent).
The last star in the line is Epsilon (e) Aquarii. From Epsilon move just under 3 degrees SE to NGC 6981 (M72). This globular cluster is one of the faintest clusters on Messier's list, appearing as a light spot in a small group of stars through my 10" scope. It may be easier to find by imagining a line from Theta (q) Capricorni to Epsilon Aquarii, M72 is just over halfway to Epsilon and off to the right.
From M72 move 1 degree to the east for NGC 6994 (M73) that consist of four stars; three form a triangle with the fourth just off the apex. 1½ degrees NE of M73 is NGC 7009 the Saturn Nebula. This one is worth finding. It is blue-green in color and although it is small it is very bright, with protrusions on each side that make it resemble the planet Saturn.
Travel back along the line of stars towards the Water Jar to Beta (b) 22 Aquarii (2nd star from the western end). From Beta move 4¾ degrees north and just to the east for NGC 7089 (M2) this is a beautiful globular cluster with a very tight core and several streamers around it.
Hop down to Fomalhaut (24 Alfa (a) Piscis Austrinus) in the Southern Fish. Fomalhaut is the brightest star in the area at magnitude 1.2. Move NW 4½ degrees to 18 Epsilon Piscis Austrinus then 6½ degrees just to the west of north to 59 Nu (n) Aquarii. This is a long series of hops but you are now just 1 degree away from the closest planetary nebula to the Earth. Move 1 degree to the west and you will find the Helix Nebula. It is pretty faint but an OIII filter really makes it look good. If you have trouble seeing it, move your scope slightly back and forth and your eye will pick out this huge ring in the sky. Visually you don't see the colors shown in the pictures but this does not change the fact that this is one extremely large and intricate object worth looking for.
After a good long look at the Helix return to the Water Jar and travel 9 degrees SE to 90 Phi (f) Aquarii then 3 degrees SSE to a group of three stars that you can see naked eye at a very dark site. These stars are Psi (y) Aquarii 1,2&3. From here move ½ degree NNW to NGC 7606, a 10.8 magnitude galaxy. NGC 7606 is a faint, elongated galaxy, with two arms and a slightly brighter center. From NGC 7606 move 6 degrees SE to the northern-most star in another group of three (this group is more open than the previous group). You will find NGC 7723 just to the north about 1 degree. NGC 7723 is hard to see at magnitude 11.2 but you can identify it because it lies less than ½ degree NE of a double star. Continue one more degree north to find a much brighter galaxy NGC 7727, a fairly bright irregular galaxy with a diffuse nucleus that fades out to the outer regions.
Aquarius has many more galaxies within its borders. Most are dimmer than 12th magnitude, but then again the hunt is half the fun.
So, until next month,
Happy Star-Hopping...Eric Reichenbach
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Lasted Updated: 12/1/2000
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