Arecibo Radio Telescope

Arecibo Radio TelescopeThose who see the Arecibo radio telescope for the first time are astounded by the enormousness of the reflecting surface, or radio mirror. The huge "disk" is 1,000 feet in diameter, 167 feet deep and covers an area of about 20 acres.

Photo by: NAIC-Arecibo Observatory, a facility of NSF, and David Parker/Science Photo Library