Star trackers https://en.m.wikipedia.org/wiki/Star_tracker https://en.m.wikipedia.org/wiki/Star_tracker Ironically, the last one I touched was a piece of donat

Star trackers https://en.m.wikipedia.org/wiki/Star_tracker https://en.m.wikipedia.org/wiki/Star_tracker Ironically, the last one I touched was a piece of donated Russian equipment, intended for spacecraft use, with no manual.