(CNN) -- We've just landed a washing machine-sized robot on a comet and NASA's chief scientist has no idea. Dr Ellen Stofan is deep in conversation with a journalist when, unable to contain himself any longer, an adviser with phone triumphantly held aloft blurts out: "Rosetta -- It's landed!" "Wonderful" Stofan beams, and the handful of reporters gathered in a lecture theater at University College London excitedly fidget in their seats. Barely has the probe touched down on a comet 310 million miles from Earth, then one of science's great minds is discussing humanity's next cosmic milestone. Stofan wants to land a man on Mars by the mid-2030s.
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NASA chief scientist, Ellen Stofan, wants humans on Mars by mid-2030s
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Astronauts would take 8 months to reach planet, face radiation, thin atmosphere
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Studying Mars would help us better understand Earth
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Believes there must be intelligent life in our universe
Indeed, life on the '@placeholder' may not just be the stuff of science fiction.