Telescope earliest existing record of a telescope was a 1608 patent submitted to the government in the Netherlands by Middelburg spectacle maker Hans Lippershey for a refracting telescope. The actual inventor is unknown but word of it spread through Europe. [[Galileo Galilei|Galileo]] heard about it and, in 1609, built his own version, and made his telescopic observations of celestial objects. The idea that the [[Objective (optics)|objective]], or light-gathering element, could be a mirror instead of a lens was being investigated soon after the invention of the refracting telescope. The potential advantages of using [[parabolic reflector|parabolic mirrors]]—reduction of [[spherical aberration]] and no
Giacomo Badoer Giacomo Badoer Giacomo Badoer (c.1575 – c.1620) was a French-born diplomat, of Venetian parentage, and pupil of Galileo Galilei. Badoer studied mathematics with Galileo in Padua in 1598/9. He later supported Galileo in 1607, in a priority dispute with Baldassarre Capra over the invention of a military compass. Badoer was one of the correspondents of Paolo Sarpi in Venice, who towards the end of 1608 was making enquiries about the invention in the Netherlands of the telescope. Badoer wrote back in Spring 1609 from Paris to Sarpi with news of the commercial telescopes then being sold; it is said that