Arizona University is the institution we have to thank for both the mirror lab and Biosphere 2. I could have passed on the mirror lab but John was adamant about us seeing it. He certainly understood all the technology connected with mirror and telescopes than I did! The lab is located under the football stadium of the university. Our tour gave us a behind the scenes look at the optical technology and the processes which are needed to make giant telescope mirrors. The mirrors in the lab are currently being made for an observatory in Chile. We saw the large oven in which one mirror is currently being heated and spin casted. In another room we saw two more mirrors sitting in their molds, one of which has undergone grinding and polishing. About as much as I got out of the tour is that the process is slow and exact, also very costly. One of the mirrors we saw has a price tag of 30 million dollars. Which leads me to Biosphere 2 (our earth is Biosphere 1). The existence of that giant greenhouse was made possible through the largess of a wealthy Texan. He laid out 50 million for that research lab which lies outside of Tucson. It sits on a rather large campus.