Researched
The telescope
Dutch lens makers sought the first telescope patents in 1608; from 1609 Galileo used one to see Jupiter's moons, lunar mountains and Venus's phases.
Open in the interactive tree →Galileo's observation of moons orbiting Jupiter (January 1610) showed that not everything circles Earth. Newton's reflecting telescope (1668) avoided colour errors; larger mirrors, photography and electronic detectors later brought stars, galaxies and the expansion of the universe into reach.
Prerequisites
- Geometry (Euclid)~300 BC
- Glassmaking & Glassblowing~50 BCTelescope lenses need clear, workable glass
- Eyeglasses~1286The telescope was invented by Dutch spectacle makers using ground lenses