Cloisters February 2007
Star Lore
Mark Toner
The constellation of Ursa Major, the Great Bear, is visible to northern hemisphere observers every clear night. Most people do not recognise the whole constellation but can easily find the 7-star pattern of the Big Dipper or the Plough. The two stars at the far end of the ploughshare or the dipper bowl, form a line that leads to Polaris, the north pole star in Ursa Minor, the Little Bear. Polaris marks the direction of north in the night sky and was extremely useful to ancient sailors when they ventured out of sight of land.
Opposite the Plough in the northern sky, you will find the big 'W' or 'M' of Cassiopeia, the Lady in the Chair. She was the mythical queen of Ethiopia, who boasted that her daughter Andromeda (next to Pegasus on the map) was more beautiful than the goddess Thetis. In revenge, Thetis sent a sea-monster Cetus to ravage the land. The only appeasement she would accept was that Andromeda be chained to a rock and left for Cetus to devour. Fortunately the hero Perseus, fresh from slaying the gorgon Medusa, came by on his flying horse Pegasus and slew the monster, saving Andromeda and claiming her for his bride. You can see Cassiopeia, the king Cepheus, Andromeda, Cetus, Perseus and Pegasus in this rich part of the sky. Andromeda also hosts the Andromeda Galaxy. At a distance of 2 million light years, it is the farthest object that you can see with the naked eye.
Visible over the winter, Orion was a great hunter, who toured around with his charioteer Auriga and his two dogs Canis Major and Canis Minor, hunting every animal imaginable. Many of these animals are found in the sky around the constellations of Orion and Auriga. These are at their best in the winter. We see Orion fighting Taurus, the Bull. The bull is really the god Zeus, who is keeping Orion away from his daughters, the Seven Sisters of the Pleiades. Orion hopes to defeat the bull and win the love of one of these nymphs. The three stars of Orion's belt form a line leading up to Aldebaran, the red eye of the bull. Carry on up in this direction and you find the cluster of stars called the Pleiades. Those with reasonable eyesight can cou nt seven sisters, but keen-eyed individuals can find more.
If you enjoy gazing at the constellations, you will know that it is a much easier prospect when you have a nice dark sky, far away from the lights of the town (or your neighbour's insecurity lights). In most countries there is a dark skies campaign group that you can link up with and try to get sensible streetlighting in your area. This can ensure happy stargazing for generations to come. We are particularly lucky where I live, in Scotland. Not only does my local authority recognise that the night sky is a natural resource and great tourist attraction, but we also now have a national programme to support dark skies, called Dark Sky Scotland. This aims to preserve our night skies and to promote them as an attraction to the remote areas of our country.
Led by the Royal Observatory Edinburgh Visitor Centre, Dark Sky Scotland events will take place from February 2007 to Spring 2008. Family events are being organised with the Forestry Commission Scotland – the national forest estate and the Commission’s accessible visitor facilities being ideal locations from which to explore the skies. Careers Scotland is coordinating a programme of workshops for teachers to help open the eyes of pupils and parents to the night sky and the wider world of science and technology.
Deputy First Minister Nicol Stephen said: "Scotland is a "science nation" and we spend around £4 million every year on bringing science to the people. I am pleased to be able to support Dark Sky Scotland and hope that it will help grow Scotland's astronomy and space science sector."
The events will be run by a specially trained team of professional and amateur astronomers, students and teachers led by the Royal Observatory Edinburgh and the Glasgow Science Centre – which have a wealth of experience in stargazing and planetarium shows.
More information on Dark Sky Scotland can be found at the official website.