Nearly three years after the rapid unplanned disassembly of the Arecibo radio telescope, we finally have a culprit in the collapse: bad sockets ... the molten zinc “spelter socket” was ...

The proximate causes of the collapse have been known for a while, including the most obvious and visible one, the failure of the zinc “spelter sockets” that were cast around the splayed ends ...

in the telescope's cable spelter sockets. Unfortunately, this issue was not identified during the post-Maria inspection, which meant engineers hadn't considered the degradation of these mechanisms ...