After building his first telescopes, Galileo demonstrated the new instrument ... That discovery helped support a heliocentric model of the solar system — a belief so radical at the time that ...

Well, any of us who has ever looked through a telescope could say the same, for the two principal types in use today were developed by giants: the refractor by Galileo and the reflector by Newton.

The unremarkable-looking object is in fact one of the most important artifacts in the history of science: it's one of only two surviving telescopes known to have been made by Galileo Galilei ...