The Big Dipper is the familiar bright seven-star asterism in the constellation Ursa Major, known in Britain
as the Plough. The five middle stars are all moving through space together
as part of a loosely-bound group known as the Ursa
Major Moving Cluster. Alkaid (Eta, leftmost
star in diagram) and Dubhe (Alpha), however,
are moving in their own directions, ultimately dooming the Dipper's shape.
|How the Big Dipper's shape will change over the next