‘Long-term zinc creep-induced failure in the 57-year-old telescope’s cable spelter sockets was the root cause of the telescope’s collapse, the report says. Sockets filled with zinc held in place a set of cables suspending the telescope’s main platform over the reflector dish. Gradually the zinc lost its hold on the cables and allowed several of them to pull out, leading to the collapse of the platform into the reflector. …’ (via National Academies )