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.
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Question: Category: PASTIMES 
Clue: The FCC assigns call signs, like N8DNR, to use in this hobby

Answer: ham radio


Question: Category: ASTRONOMY 
Clue: A galactic cloud of dust & gas, its name comes from the Latin for "cloud"

Answer: nebula


Question: Category: 1997 
Clue: James Fenimore Cooper would like this spacecraft that became the first to land on Mars in over 20 years

Answer:
pathfinder