PALMDALE, CA - MAY 20: The DC-8 Airborne Science Laboratory, used in research missions involved in the Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS II) flight experiment, is seen... more 
PALMDALE, CA - MAY 20: The DC-8 Airborne Science Laboratory, used in research missions involved in the Alternative Fuel Effects on Contrails and Cruise Emissions (ACCESS II) flight experiment, is seen in the NASA Armstrong Flight Research Center hangar on May 20, 2014 in Palmdale, California. NASA provided a behind-the-scenes tour of the NASA Armstrong Flight Research Center's hangar in Palmdale, California, and the center's main campus at Edwards Air Force Base to news media representatives. (Photo by David McNew/Getty Images) less 
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Getty Images | Photo By David McNew / Getty Images
Wed, May 21, 2014 8:02 AM EDT