When we look at the night sky, light rays given out by millions of stars can be seen. From earliest times, people have looked at those stars and found patterns or constellations. Constellations we see, depends upon where we are standing on Earth.
Stars move through space but lie at very great distances from each another. Their positions hardly alter over centuries. The stars in a constellation are not really clese together. They all lie at different distances and only appear close to each other as they are situated in roughly the same direction as seen from Earth.
There are a total of 88 constellations. Some of these, like Orion ( the Hunter ) and Ursa Major ( the Great Bear ), are easy to locate. However there are some which are small and faint.
Distance of the Stars
The first star to have its distance measured can be found in the counstellation of Cygnus, the Swan. This was worked out by the German astronomer Friedrich Bessel in 1838. He found that the star was about 11 light years away.