Why was the Space Shuttle retired?
Sadly the Space Shuttle turned out to be just too dangerous.
The disasters that destroyed the Challenger shuttle on launch in 1986, and the Columbia on re-entry to Earth’s atmosphere in 2003, were both caused by damage to the main orbiter during launch.
It turned out that the shuttle design – which strapped the orbiter to the side of its booster rockets and fuel tank – was much riskier than traditional space vehicles where crew and cargo sit in a capsule on top of the rocket stages.
Since the shuttle was retired in 2011, a variety of unmanned launch vehicles have taken its place for satellite launches, while Russian Soyuz spacecraft take crews to and from the ISS. NASA is currently investigating other possible long-term replacements for manned spaceflights.
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