In the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, workers monitor the progress of external fuel tank, ET-122, for space shuttle Endeavour's STS-134 mission as it is being attached to the twin solid rocket boosters on the mobile launcher platform.
Endeavour and its crew will deliver the Express Logistics Carrier-3 and the Alpha Magnetic Spectrometer to the International Space Station. Launch is targeted for April 19. For more information visit, http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Jack Pfaller