The space shuttle program was a paradigm of rocket science—here we see the Space Shuttle Discovery on its April 5, 2010 launch. The space shuttles employed twin solid rocket boosters during launch, each of which ignited to send the shuttle and its crew into space. From the first launch in 1981 to the final in 2011, the space shuttle fleet flew a total of 135 missions. After concluding its mission in space, the space shuttle orbiter would essentially land as an “unpowered glider” back on Earth. Because of this, NASA points out that every landing had to be perfect. For the most part, they were.