This image provided by NASA TV shows the space shuttle Discovery on the launch pad at Kennedy Space Center Friday morning Dec. 17, 2010 as a tanking test begins. Teams will fill the spacecraft’s external fuel tank with liquid hydrogen and liquid oxygen just as they do during a launch attempt to verify repairs made to the tank. Technicians added 89 sensors to the outside of the tank recently including strain gauges to gather precise measurements of how much the tank moves during the fueling process. (AP Photo/NASA)
