Just a few years after the shuttle Challenger explosion in 1986, the great space debate centered on what to do next. Were manned missions worth the risk? And if so, where should NASA point its rockets? Many scientists thought the moon could be a launching pad for interplanetary travel, but Franklin D. Martin, an administrator in NASA's Office of Exploration, was already looking to Mars. He proposed studies on the human body in low and artificial gravity and envisioned sending rovers to Mars to image the planet and collect samples in advance of a manned mission.
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