History of Telescopes

Galileo

Aug 25, 1609

used two lenses in a long tube to view objects ten times further away.

Isaac Newton

Nov 19, 1668

built the first reflecting telescope

William Herschel

Mar 6, 1772

built a large reflecting telescope with a four-foot diameter mirror

Oberth and Spitzer

Jul 10, 1920

Hermann Oberth proposed the idea of a space-based telescope
in 1920 which was expanded by Lyman Spitzer.

Copernicus

Aug 21, 1972

The first space telescope was launched