Since radio waves are longer than optical waves, radio telescopes are made differently than the telescopes used for visible light. Radio telescopes must be physically larger than an optical telescopes in order to make images of comparable resolution. But they can be made lighter with millions of small holes cut through the dish since the long radio waves are too big to "see" them. The Parkes radio telescope, which has a dish 64 meters wide, cannot yield an image any clearer than a small backyard optical telescope! LIGO was originally proposed as a means of detecting these gravitational waves in the 1980s by Rainer Weiss, professor emeritus of physics from MIT Kip Thorne, Caltech’s Richard P. Feynman Professor of Theoretical Physics Emeritus and Ronald Drever, professor emeritus of physics, also from Caltech.
