Arecibo Telescope
The Arecibo Telescope was the world’s largest single-aperture telescope for 53 years, until it was surpassed in July 2016 by the Five-hundred-meter Aperture Spherical Telescope in Guizhou, China. The telescope’s main collecting dish had the shape of a spherical cap 1,000 feet in diameter with an 869-foot radius of curvature. The observatory, funded primarily by the National Science Foundation with...