The STS-135 crew members express their gratitude to the thousands of workers who have processed launched and landed during an employee appreciation event.

In front of Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida the STS-135 crew members express their gratitude to the thousands of workers who have processed, launched and landed the space shuttles for more than three decades during an employee appreciation event. Seen here is Commander Chris Ferguson shaking the hand of Kennedy Space Center Director Bob Cabana. Atlantis' final return to Earth occurred at 5:57 a.m. EDT July 21, 2011.

Securing the space shuttle fleet's place in history, Atlantis marks the 26th nighttime landing of NASA's Space Shuttle Program and the 78th landing at Kennedy. Atlantis and its crew delivered to the International Space Station the Raffaello multi-purpose logistics module packed with more than 9,400 pounds of spare parts, equipment and supplies that will sustain station operations for the next year. STS-135 is the 33rd and final flight for Atlantis and the final mission of the Space Shuttle Program. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Kim Shiflett