Endeavour's astronauts put and check the fit of their helmets and gloves before heading to the Astrovan for the ride to Launch Pad 39A.

In the Operations and Checkout Building (O&C) at NASA's Kennedy Space Center in Florida, space shuttle Endeavour's STS-134 astronauts put on their launch-and-entry suits and check the fit of their helmets and gloves before heading to the Astrovan for the ride to Launch Pad 39A. Pilot Greg H. Johnson, seen here, last piloted space shuttle Endeavour during its STS-123 mission in 2008.

STS-134 will deliver the Alpha Magnetic Spectrometer-2 (AMS), Express Logistics Carrier-3, a high-pressure gas tank and additional spare parts for the Dextre robotic helper to the International Space Station. May 16 at 8:56 a.m. will be the second launch attempt for Endeavour. The first attempt on April 29 was scrubbed because of an issue associated with a faulty power distribution box called the aft load control assembly-2 (ALCA-2). STS-134 will be the final spaceflight for Endeavour. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts134/index.html. Photo credit: NASA/Kim Shiflett