View Single Post
KenJackson
#15
Jul9-11, 02:01 PM
P: 19
I can't condemn the condemnation of any project that runs so far over budget.

But it should be noted why this thing cost so much to begin with. I think it was this article in Scientific American magazine (though I can't seem to access it now even though I subscribe) that explained how they are making those beautiful mirrors.

They are made out of beryllium because it's so lightweight. But like everything, they will warp when subjected to near absolute zero of space. So how do they account for the warping? They ship the pieces to some facility in Huntsville, Alabama that lowers the temperature to something like 50K while they measure the warping and compare with what it has to be to get an in-spec image. Then they ship it back and grind it some more. And the cycle repeats.