John Grunsfeld, associate administrator for the Science Mission Directorate, NASA Headquarters, Washington, introduces a panel to discuss the upcoming launch of the Mars Atmosphere and Volatile Evolution (MAVEN) mission, at a press conference at NASA Headquarters in Washington on Monday, Oct. 28th, 2013. MAVEN is the agency's next mission to Mars and the first devoted to understanding the upper atmosphere of the Red Planet. (Photo credit: NASA/Jay Westcott)