Mariner IX took two photos of Mars’ north pole.
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NASA's Pathfinder Space probe landed on Mars.
NASA celebrated April Fool's Day by telling the world that they found water on Mars.
NASA launched the Mars Science Laboratory probe, which carried the Curiosity Rover to Mars.
America's robot spacecraft, the Viking I, successfully landed on Mars.
NASA's Mars Odyssey completed its 60,000th orbit around Mars.
