Dark clouds fill the sky behind the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. 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. Weather concerns caused a scrub July 12 as well. Endeavour will deliver the Japanese Experiment Module's Exposed Facility, or JEM-EF, and the Experiment Logistics Module-Exposed Section, or ELM-ES, in the final of three flights dedicated to the assembly of the Japan Aerospace Exploration Agency's Kibo laboratory complex on the International Space Station. STS-127 is the 29th flight for the assembly of the space. Photo credit: NASA/Tim Jacobs