[Feature] The biggest ear
China's awesome Five-hundred-meter Aperture Spherical radio Telescope, the world's largest of its kind, will be able to peer further into the past than previous radio telescopes to gather weaker and more distant signals that promise to provide clues to the origins and evolution of the universe, probe gravitational waves and dark matter, and listen for transmissions from extraterrestrial civilizations. Building the instrument required solving a host of engineering problems, ranging from dealing with a remote, barely accessible site, shielding the dish from radio frequency interference that would drown out the signals from cosmic objects, and developing a first-of-its-kind method to pull a portion of the spherical dish into a gradually moving paraboloid to aim at and track astronomical targets as Earth rotates. Fulfilling the telescope's promised capabilities will mean solving one more engineering challenge in getting that shape-shifting scheme working as planned. Author: Dennis Normile