For thousands of years, stargazers have seen shapes formed by
the stars in the night sky. These shapes serve as guideposts for astronomers as
they navigate their way across the night sky in search of celestial objects.
Star patterns such as the hunter Orion and the winged horse Pegasus are commonly
called constellations, but the term constellation in modern astronomy actually
refers to a particular region of the sky. The star figures first noticed in
antiquity lie within these regions.
Some constellations hold other identifiable shapes formed by
stars, called asterisms. For example, seven bright stars within the
constellation Ursa Major form what may be the most renowned asterism that many
call the Big Dipper. In 1930, astronomers divided the sky into 88
constellations, giving each a Latin name.