CAPE CANAVERAL, Fla. – A model rocket built by students of the International Space University parachutes back to Earth during the rocket launch competition of the ISU's summer session. The competition was conducted at Launch Complex 39A at NASA's Kennedy Space Center in Florida, which co-hosted this year's ISU. Six teams designed and built large model rockets, each between three and five feet tall, and launched them from Launch Pad 39A, the starting point for Apollo missions to the moon and dozens of space shuttle flights. Each launch carried a raw egg, dubbed "eggstronauts" and had to recover it intact to be declared successful. Photo credit: NASA/Charisse Nahsser KSC-2012-3850

The Space Shuttle program was the United States government's manned launch vehicle program from 1981 to 2011, administered by NASA and officially beginning in 1972. The Space Shuttle system—composed of an orbiter launched with two reusable solid rocket boosters and a disposable external fuel tank— carried up to eight astronauts and up to 50,000 lb (23,000 kg) of payload into low Earth orbit (LEO). When its mission was complete, the orbiter would re-enter the Earth's atmosphere and lands as a glider. Although the concept had been explored since the late 1960s, the program formally commenced in 1972 and was the focus of NASA's manned operations after the final Apollo and Skylab flights in the mid-1970s. It started with the launch of the first shuttle Columbia on April 12, 1981, on STS-1. and finished with its last mission, STS-135 flown by Atlantis, in July 2011.