In 1969, after the space race was won, the excitement died down about sending astronauts to the moon. It was expensive to send fully-equipped rockets and astronauts up, and since America had already won the space race the extensive costs were growing less validated. To keep ahead in terms of astronautical technology, NASA had to come up with something groundbreaking but less expensive that could also be useful. This was when the idea of the 'space shuttle' was born. A reusable booster that came off a rocket as it launched, its massive cargo space meant it could carry satellites, repair gear and have a fully stocked science laboratory. Because of its reusability, it would have less cost than a fully-fledged rocket.
Early on in the progress of the Space Shuttle Columbia, it came across faults. It was designed to go into low orbit, which meant it should be lighter than a rocket. Because of the fact that it also wasn't going to go as fast as a rocket when re-entering Earth's atmosphere. This meant that it needed to have more protection. The aluminium heat shields that helped protect the rocket wouldn't be effective on the shuttle, the aluminium sheets on the underside of the shuttle going to melt and bend. They needed to have something light and heat durable that could be easily applied to a shuttle going into low orbit. They covered the shuttle with LI-900 silica tiles that were designed to prevent ice forming and be heat-durable enough to ensure that the aluminium would hold while re-entering. These silica tiles were very brittle, which meant they were each cut into six-inch pieces so that they wouldn't crack further. Eventually, the shuttle was covered in 25,000 of these. While in space, six of these came off. They made it past the re-entering stage, just barely.
This was regarded as a wide success and in the following years NASA built a fleet of shuttles. They were named the Space Shuttle Columbia, Challenger, Atlantis, Discovery, Endeavour and a prototype named Enterprise. They completed 135 missions successfully. The program eventually ended because of the Challenger explosion; the O-rings which were designed to keep the gas from escaping outwards through pressure from the gas had frozen, which meant less flexibility. During the launch, it exploded due to this failure to keep the gas inside by the O-rings, which had frozen. After the Challenger disaster, the program was called off.
The programs' end wasn't just because of that; the promised low costs hadn't been as low as they thought, and it was beginning to get expensive. The shuttle and ISS had taken up all of NASA's budget, to the point that no significant developments had been made possible. If they both stayed, NASA's budget would remain flat - one of them had to go. The ISS had just begun to show signs of promise for research, so the shuttles were scrapped instead. The question that I have: should NASA reinstate the Space Shuttle program in hopes of further development on the ISS, regardless of the talked about retirement for the ISS, or should the Space Shuttle program remain dormant?