History of Manned Spaceflight - Part 3: SPACE SHUTTLE
NASA's space shuttle fleet began setting records with its first launch on April 12, 1981 (exactly 20 years to the day after Gagarin’s flight !) and continues to set high marks of achievement and endurance. Starting with Columbia and continuing with Challenger, Discovery, Atlantis and Endeavour, the spacecraft has carried people into orbit repeatedly, launched, recovered and repaired satellites, conducted cutting-edge research and built the largest structure in space, the International Space Station.
As humanity's first reusable spacecraft, the space shuttle pushed the bounds of discovery ever farther, requiring not only advanced technologies but also the tremendous effort of a vast workforce. Thousands of civil servants and contractors throughout NASA's field centers and across the nation have demonstrated an unwavering commitment to mission success and the greater goal of space exploration The shuttle program is scheduled for mandatory retirement in 2011 and the launch of the final scheduled flight is targeted for the end of June. STS-135 will be the 37th mission to the ISS.