A series of radio antennas can produce an image equal to that of a telescope 22 miles across.
Radio telescopes receive radio waves emitted by celestial bodies -- stars and other objects in space -- and convert those signals into images using computers and video displays. Radio signals from far away are very weak and require very large receivers to detect. Since a single receiver big enough to collect signals from many light-years away would collapse under its own weight, engineers at the National Radio Astronomy Observatory created the Very Large Array (VLA). Twenty-seven, 82-foot-diameter dishes combine their signals to produce an image equal to one made by a telescope 22 miles across. The Array's dishes are linked by cable, which makes it the world's largest of this type.
Learn more about the Very Large Array.