To appreciate just what it took to actually make this gadget work, it is interesting to follow... if not every minute.. this re-broadcast of the live action as they finish deploying the mirrors.
   The entire program is about 4 hours, but one can skip ahead by tapping the progress bar. At about 1 hr. 50 min. they interview one of the technology managers, who explains in detail what it took to create the thing. It is amazing that it took ONLY 20 years.

https://www.youtube.com/watch?v=tlGTem8vkB0