STS-121 Discovery KSC One Five

This mission to the International Space Station was the second return-to-flight mission after the Columbia tragedy, and the first to return to the Shuttle Landing Strip at Kennedy Space Center. It also delivered a third astronaut to the International Space Station. The ISS crew had been reduced to caretaker status, with only two astronauts aboard due to the lack of incoming shuttles. Post-Columbia, shuttle flights had been grounded. This was the most photographed mission ever. That allowed NASA engineers to verify their foam-shedding fixes and continue the remaining flights to complete the ISS. Columbia and her final crew’s sacrifice is honored by the survival and continuance of the American space effort.