In Astronomy, what does the "Seven Sisters" refer to?

More Questions:

What sport's most famous series is played for the Ashes urn?

In 1975, what re-opened after an 8 year closure?

Which UK politician was given the nickname Tarzan?

The Mario villain "Wario', made his first appearance in which Nintendo game?

Who wrote the 1952 novel "The Bridge over the River Kwai"?

In a nursery rhyme, whose wife "Could eat no lean"?

What children's classic first chapter is titled "The Boy Who Lived"?

Where is Gorky Park?

Who originated the Uncertainty Principle?

Which is larger, the U.S. gallon or the Imperial gallon?

What is the maximum number of lines of symmetry a rectangle can have?

What is a whale's leap out of the water called?

What was the name of the Argentine cruiser sunk after a British attack during the Falklands War in 1982?

The Battle of Palo Alto was the first major battle of what war?

What was U.S. President Wilson's first name?