WASHINGTON, DC - APRIL 22: NASA Administrator Charles Bolden delivers the opening keynote address at the Humans to Mars Summit on April 22, 2014 at George Washington University in Washington, DC. With... more 
WASHINGTON, DC - APRIL 22: NASA Administrator Charles Bolden delivers the opening keynote address at the Humans to Mars Summit on April 22, 2014 at George Washington University in Washington, DC. With the goal of sending a manned spacecraft to Mars within the next two decades the summit helps promote the improvement of technologies that will make travel to the planet more feasible. (Photo by Win McNamee/Getty Images) less 
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Getty Images | Photo By Win McNamee / Getty Images
Tue, Apr 22, 2014 10:23 AM EDT