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Photographs do more than document history -- they make it. At TED University, Jonathan Klein of Getty Images shows some of the most iconic, and talks about what happens when a generation sees an image so powerful it can't look away -- or back.
Joel Levine: Why we need to go back to Mars - Joel Levine (2009)
At TEDxNASA, planetary scientist Joel Levine shows some intriguing -- and puzzling -- new discoveries about Mars: craters full of ice, traces of ancient oceans, and compelling hints at the presence, sometime in the past, of life. He makes the case for going back to Mars to find out more.