You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.

Category: HISTORIC FACES 
Clue: This man shared a Nobel Prize with his wife Marie
pierre curie

Category: I NEED SOME SPACE 
Clue: It can be a small pill or a small spacecraft like the Mercury ones used by early astronauts
a capsule

Category: MEET AL GORE 
Clue: Al's 1992 treatise on the environment was titled this "in the Balance"

earth