As clouds begin to gather over the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida, the convoy command and SCAPE vehicles are in position in the event of a return-to-landing-site is needed after launch of space shuttle Endeavour on the STS-127 mission. NASA managers postponed today’s space shuttle launch because of lightning and thunderstorms within the 20-nautical-mile circle around the launch pad. The fifth launch attempt for the STS-127 mission was scrubbed at 6:39 p.m. EDT. The first two launch attempts on June 13 and June 17 were scrubbed when a hydrogen gas leak occurred during tanking due to a misaligned Ground Umbilical Carrier Plate. Mission managers also decided to delay tanking on July 11 for a launch attempt later in the day to allow engineers and safety personnel time to analyze data captured during lightning strikes near the pad on July 10. The fourth attempt on July 12 was scrubbed due to weather concerns as well. Photo credit: NASA/Chuck Tintera