Echo 1a was a 100 foot balloon launched into space and inflated. Echo 2 was even larger. They were Mylar, coated with shiny material. It was launched to reflect radio signals back to Earth.
Some (including myself) have suggested similar designs for space based solar power satellites. One hemisphere could be transparent, and the other reflective to focus light toward some sort of reflector.
Here's my question: Could the hemispherically reflective balloon be used to focus light onto optical sensors? Could we inflate a telescope in space that'd be hundreds of feet in diameter?
I remember the 'trouble with Hubble'. Would the accuracy of the geometry of the telescope matter too terribly much with a telescope this size?
I don't know much about telescopes, so I apologize if these are stupid questions. If it make for a good telescope, then I'd like to know why. I've been thinking about this for a long time. Obviously there's something wrong with the idea; I imagine it's that the curvature of the balloon would be too unpredictable.