Beemer, shown at the Mars Society's Mars Desert Research Station in Utah in 2011, is a candidate for both Mars One and the Mars Arctic 365 program. Max Fagin hide caption

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The Orion capsule is poised to make its first test flight Thursday. If all goes as planned, the unmanned vehicle will orbit Earth twice before splashing into the Pacific Ocean. Kim Shiflett/NASA hide caption

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A member of the Indian security force keeps watch over a launch vehicle carrying the Mars Orbiter probe at the Indian Space Research Organization facility, in Sriharikota, in 2013. AFP/Getty Images hide caption

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In this artist concept provided by NASA, the MAVEN spacecraft approaches Mars on a mission to study its upper atmosphere. AP hide caption

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Japan Aerospace Exploration Agency astronaut Aki Hoshide makes a space walk outside the International Space Station in 2012. NASA/Getty Images hide caption

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NASA's MAVEN, short for Mars Atmosphere and Volatile Evolution, with a capital "N" in EvolutioN, atop a United Launch Alliance Atlas V rocket, lifts off from Cape Canaveral Air Force Station, on Monday. John Raoux/AP hide caption

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Scientists and engineers work on the Mars Orbiter at the Indian Space Research Organisation's satellite center in Bangalore, India, on Sept. 11. The spacecraft is scheduled to be launched sometime in the next three weeks. Manjunath Kiran/AFP/Getty Images hide caption

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A photo composed of nearly 900 images taken by the rover Curiosity shows a section of Gale Crater near the equator of Mars. The rovers are continuing to work through the U.S. government shutdown. NASA/AP hide caption

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