Mythology influenced the naming of many celestial bodies including the constellations and the names of the main constellations have changed little since ancient times. Star patterns within the constellations will always stay the same as, like the Sun, they move across the sky, from east to west. However, different constellations will be seen in the sky, depending on the season.
The easiest way to learn the constellations is by using a star chart and once you are able to pick out a few of the more familiar constellations; these can be used as a reference point to find other star patterns.
The plough, for instance, is visible all year round if you live in the northern hemisphere and this is one of the easiest star patterns to recognise. This group of stars is also known as the Big Dipper or the Saucepan (recognise it now?) The Big Dipper is an asterism that forms a part of the Big Bear constellation and at the very top of the Big Dipper is the nose of the Great Bear. The bowl-like shape of the Big Dipper (or Saucepan) represents a part of the Great Bear’s back with its handle representing the bear’s tail. (An asterism is a star pattern that may be seen within one constellation or that is formed of stars belonging to a number of constellations.)
Being aware of the myths behind the star patterns and constellations can also help you recognise and remember their star patterns in the night sky.
Why, according to Greek mythology, is there a Great Bear in the sky? The tale is a one that once heard, will probably always be remembered. It goes like this: Zeus once fell in love with a mortal woman called Callisto who was a traveller and a huntress. His jealous wife changed the huntress into a large bear. When Callisto did not return from a long journey, her son, Arcas set out to find her and one day he met a huge bear in a forest. To his horror, the bear started to run towards him and not knowing it was his mother, his natural reaction was to aim an arrow towards her. Just as he was going to fire the arrow, Zeus interceded and changed Arcas into a smaller bear. He then grabbed both bears by their tails, swung them round and threw them into the sky where they would remain safe and immortal. When Hera discovered this, she moved the bears to a portion of the sky that never sets so Callisto and Arcas would never get a break from shining, until the end of the world.
From the Plough (or Big Dipper) it is easy to find the North Star. This star is important for navigation purposes as it sits directly over the North Pole. Imagine the Big Dipper as a saucepan and find the two stars that form the side of the pan opposite the ‘handle.’ As these stars point up away from the pan, five times their distance away will be found the North Star. This never changes.
Orion is a bright star that dominates the winter’s night sky. Orion, in mythology is known as ‘the hunter’ and an easy way to learn this constellation is to imagine it as making up a figure of a man. Central to this figure are the three stars that make up the hunter’s belt. These stars line up in a unique way and there is no other grouping of stars like it. Once you have found Orion’s belt, you might distinguish other stars in this constellation such as Betelgeuese, a bright star on Orion’s left shoulder. Once you find Orion’s belt you should have no trouble finding this constellation again.
From Orion’s belt, it is easy to locate other constellations. To find Gemini, for instance, firstly locate Orion’s belt, then move your eyes upwards to re-locate Betelgeuse on the hunter’s shoulder. Further past this star will be Castor and Pollux, Gemini’s twins.
Gemini is the most northerly constellation of the zodiac. Think of the astrology sign Gemini, the symbol of which is the Twins. This constellation is dominated by two bright stars that represent the heads of the twins. The myth goes that when Castor was killed and Pollux was left grief stricken, Zeus took pity on the twins and granted that they could share their immortality by living alternating lives between heaven and earth, thus their place in the heavens was secured.
So, Gemini neighbours the constellation of Orion and is located to the North West of Orion. Another way to find the constellation of Gemini is to draw a line from the Big Dipper’s four stars and this will take you to Pollux, Gemini’s brightest star. To the right of Pollux, will be Castor.
Now you can recognise Orion’s belt, there are other constellations you can find, using this as a reference point. Draw a line down from the star on the bottom left of Orion’s belt and this will take you to the bright star Sirius in the constellation of Canis Major.
Sirius, the brightest star in the night sky is also known as the Dog Star, one of Orion’s hunting dogs. According to myths, the Sun god Apollo was jealous of Orion because of Artemis’s (goddess of the hunt and wild animals) love for him. Apollo teased Artemis about her archery skills and challenged her to hit a spec out in the ocean. The speck was Orion swimming and Artemis killed Orion with a single arrow. When she realised this, she was overwhelmed by guilt and placed him up in the heavens as a constellation. His faithful hunting dog, Sirius would not give up on his search for his master so Artemis placed him in the heavens at Orion’s heels. Thus his also being called the Dog Star!
Learning the myths behind the constellations (and a little research will reveal many more) makes it far easier to locate the stars and to remember their names and their relationships with each other.
Sources
http://homepage.mac.com/kvmagruder/bcp/aster/constellations/index.html
http://www.sky-watch.com/astronomy-guide/learning-the-constellations.html
http://www.astronomytoday.com/astronomy/constellations.html
http://www.astromax.org/con-page/con-88.htm
http://homepage.mac.com/kvmagruder/bcp/aster/general/asterism.htm
