I’m not sure where I was twentyfive years ago when the Challenger space shuttle exploded slightly more than sevnety seconds into its launch, but I do remember that I felt devastated when I first heard the news. Even at age eleven I was a science fiction reader and space fan and the shuttle was supposed to be how we were going to get a proper space programme and L5 O’Neill colonies and ultimately the stars. They were not supposed to blow up! It was only much, much later that I understood how much of a kludge the shuttle was and how it was possible for Challenger to blow up. The documentary above was made by NASA in 1986, after investigations into the explosion had concluded. It tells how the shuttle exploded, but not why, what the root causes were. That would take much more time.