Sometimes, when retirement bores me, I search ebay for words such as eyepiece, telescope, observatory, and planetarium---highest price first.
This time I found something very interesting under "planetarium". I wish I had enough use for this to be worth buying it!
The skies which graced Denver's Gates Planetarium can be yours!! Whether you're looking to repair an instument or create your own (that's what I was going to do - contact me), here's an example of a fine Minolta sky which can be yours inexpensively! HEAVY FOR SHIPPING!
"BUY IT NOW" also gets you the slip-ring-equipped rotating bearing for joining the two balls together into one unit and the motor to drive it in rotation, PLUS a number of extra projectors (constellation, Milky Way, etc.)