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Old 16-11-2007, 01:13 PM
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Dooghan (Dooghan)
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Join Date: Jun 2007
Location: Rockhampton
Posts: 62
Quote:
Originally Posted by bojan View Post
This thing is patented a long time ago :-( I discovered this when I tried it years back, and it sort worked.... My problem then was I could not get hold of aluminized mylar foil).
BTW, this principle (vacuum on one side of the glass plate) is used in a process to grind the Schmidt plate for large appertures (this was published in 80's in Sky&Telescope).

However, the variation of this method may work in space - like inflating a large transparent sphere with low pressure gas.. the sphere must be partly aluminized at one side, of course....
One problem I can see with it is the sun is going to heat up the tube. That heats up the gas inside the tube and changes the shape of your mirror. Then when the tube goes into the earth shadow you've got the reverse happening. I also wonder if you air turbulence in the tube would be a problem?
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