Who Invented the Telescope?
The origin of the telescope is shrouded in mystery. Galileo, however, was not the original designer of the telescope. The Dutch were the first to use the instrument. The diary of Johannes Janssen describes the achievements of his father, Zacharias, a spectacle-maker.
About 1590, the elder Janssen discovered that a combination of a convex lens with a concave lens for an eye piece enabled its user to see distant objects, not only more clearly, but also with greater magnification a discovery that became known in history as the principle of the compound microscope.
In 1608, Hans Lippershey, a Dutch optician, made use of this new knowledge to devise a telescope. However, Lippershey did not invent this wonderful tool for seeing at great distances. His discovery was made because he had inspected an earlier telescope, one made in Italy. No one knows who the Italian designer was, but the instrument itself had the inscribed date, 1590.
Galileo heard about the Dutch telescope in June 1609, built his own within a month, and improved upon the design in the following year. In the same year, Galileo became the first person to point a telescope skyward in order to make telescopic observations of a celestial object.
It was Galileo who first saw the rings around the planet Saturn and the moons of Jupiter. These discoveries were so astounding in their time that Galileo became known as the inventor of the telescope, a misconception that persists even today.