Snapshots: The world in 24 hours, April 29

Mission Commander Mark Kelly waves as the crew of space shuttle Endeavour's mission STS-134 departs crew quarters for launch pad 39A at the Kennedy Space Center in Cape Canaveral, Florida April 29, 2011. The crew returned to their quarters before reaching the launch pad after a problem with an auxilliary power unit on the shuttle forced a launch scrub. [Photo/Agencies]