It will never work! An idea that changed infrared astronomy from space is a recent magazine article I wrote about this period soon after Tim retired. If the link direct to the journal does not work, the original word file is here . See also Davies, J.K., Hawarden, T.G., Mountain, C. M. (1991). ``Radiatively Cooled Space Telescopes, a New Direction for Infrared Space Astronomy. Acta Astronautica Vol 25 p223-228.