Seeing Better: In 400 Years, Telescopes Advance from Rooftops to Mountains to Orbit
Invention of the telescope. Claimed by Dutch lensmaker Hans Lippershey, although others (including Jacob Metius and Zacharias Janssen) are also sometimes credited.
Galileo improves the telescope anal begins using it for astronomy, starting with lunar observations.
German astronomer Johannes Kepler designs a new telescope using convex lenses.
A concave reflecting telescope is built by Niccolo Zucchi, an Italian Jesuit and physicist.
Dutch scientist Christiaan Huygens discovers Saturn's rings and its moon Titan using a Keplerian telescope with an 11-foot focal length.
James Gregory, a Scottish mathematician, describes a new type of reflecting telescope.
Isaac Newton invents a small but powerful reflecting telescope using mirrors.
Laurent Cassegrain, a French priest, invents a reflecting telescope based on Gregory's principles.
King Charles II commissions the Royal Greenwich Observatory in England.
Astronomer William Herschel uses a reflecting telescope to discover the planet Uranus; he later builds more powerful telescopes with which he discovers several moons of Uranus. Herschel's largest telescope has a focal length of 40 feet.
Harvard College Observatory is established in Cambridge, Mass.
In Ireland, William Parsons builds the Leviathan, a reflecting telescope with a mirror that is 6 feet in diameter. He uses it to discover the spiral structure of the nebula M51.
The Hale reflecting telescope is constructed atop Mount Wilson in California. At that time, it was the world's largest telescope.
The 100-inch Hooker reflecting telescope is completed at Mount Wilson. It ranks as the world's largest telescope for the next 30 years.
Grote Reber, an American radio engineer, builds the first telescope designed to observe the radio region of the electromagnetic spectrum.
British astronomer Martin Ryle builds an interferometer for making radio observations of space. …