> Additional tests performed on June 23 and 24 included turning on the backup computer for the first time in space. The tests showed that numerous combinations of these hardware pieces from both the primary and backup payload computer all experienced the same error - commands to write into or read from memory were not successful.

The engineering and circumstances around this are incredible to me. Imagine planning for this possibility decades in advance, experiencing issues and still working through it without sending a single human in to physically investigate.