The Newtonian reflecting telescope has been in use for centuries since its invention by Isaac Newton in 1668. Unlike refracting telescopes (whose lenses are very expensive), the Newtonian ...

who invented a reflecting telescope in 1668. A few experimental liquid-mirror telescopes have been built here on Earth, but the only one currently operating is the International Liquid Mirror ...

Around 1668 he managed to produce a functioning reflecting telescope using a mirror made of a copper-tin-arsenic alloy of his own devising. He cheated a little, building a spherical mirror that ...

His original reflecting telescope, which he built himself in 1668, was just six inches long. This modest device not only eliminated the colored fringes but magnified whatever it focused on by 40 ...

In 1668, he built the world’s first reflecting telescope, which had the distinction of using a curved mirror. Among his many achievements, English physicist and mathematician Isaac Newton ...

1845 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. 1908 The Hale ...

This was the first working reflecting telescope. Other designers proved unable to grind mirrors with a regular curvature, so the reflector remained largely a curiosity until the mid-18th century ...

As a result, more than a century passed before reflecting telescopes became popular among astronomers. (Image: Andrew Dunn, from Eyes on the Skies: 400 Years of Telescopic Discovery by Govert ...