Re:James Webb Space Telescope
by Florin_Andrei on Friday January 23, 2015 @02:04PM
(#8936579)
Not to diminish the achievements of the opticians working on the JWST, but you can obtain the same level of perfection at home, using everyday tools. However, you'll be working on a much smaller surface.
Make your own telescope mirror. To pass the tests, it must follow the ideal surface with an error less than lambda/4, where lambda is the wavelength of visible light. In practice, that's 0.1 microns or less. Also, the density of scratches and pits must be very low (not detectable by usual means).
It's totally doable by hand, working in your garage, on a piece of glass the size of a dinner plate. It just takes a very, very long time, at least on first attempt. My first telescope took over a year (admittedly, I took too many breaks, and then I did a lot of experiments with the techniques).
Make your own telescope mirror. To pass the tests, it must follow the ideal surface with an error less than lambda/4, where lambda is the wavelength of visible light. In practice, that's 0.1 microns or less. Also, the density of scratches and pits must be very low (not detectable by usual means).
It's totally doable by hand, working in your garage, on a piece of glass the size of a dinner plate. It just takes a very, very long time, at least on first attempt. My first telescope took over a year (admittedly, I took too many breaks, and then I did a lot of experiments with the techniques).
http://florin.myip.org/blog/150-mm-f8-mirror-25-mm-pyrex-pol...