Often in the night sky, people in the Northern Hemisphere can see the Big Dipper, a set of seven stars that have been used for centuries for navigation and testing eyesight.
Dubhe and Merak, the two stars on the front edge of the cup are important to navigators because they point directly at the North Star. Mizar, the dim star at the bend in the dipper's handle, was once used to test people's eyesight. If you could see it, your eyesight was okay.
The Big Dipper is not a constellation, it is an "asterism," which just means it is part of a constellation. Its constellation is Ursa Major, also called the Great Bear. The cup of the dipper is supposed to be the hindquarters of the bear and the handle of the dipper is its tail, though some people have commented that it is an awfully long tail for a bear.
