Magnification, the seminal feature of telescopes, was known as far back as A.D. 1000.
During the later part of the eighteenth century, while European astronomers debated the merits and deficiencies of both refracting and reflecting telescopes, the Englishman William Herschel recognized that regardless of the type of telescope, the larger the lens or mirror, the better the image created. Herschel's conclusion prompted a race among astronomers to build giant telescopes, a competition that continues to this day.
In 1932, while working for Bell Labs in New Jersey, physicist Karl Jansky made a rather unsettling discovery. Jansky's work dealt with the problems of radio and telephone communications, and he had been assigned the task of tracking down the crackling static noises that plagued early overseas telephone reception.
At the opposite end of the electromagnetic spectrum from low-energy, long radio waves are very high-energy, short X-rays followed by even shorter gamma rays, the shortest of all waves on the electromagnetic spectrum. As is the case with radio waves, X-rays and gamma rays are forms of light invisible to the eye.
In 1962, the National Academy of Sciences recommended the construction of a large optical telescope. More revolutionary than any of its predecessors, however, this one would be the first telescope rocketed into orbit to capture visible light waves.
The astonishing success of the Hubble, Chandra, and HETE telescopes whetted astronomers' appetites for resolving more complicated mysteries about the universe. Unraveling these mysteries will require further discoveries about the universe, which, in turn, will require more efficient, improved, and exotic telescope designs.