Newtonian telescope

American  

noun

1. a reflecting telescope in which a mirror or reflecting prism is mounted on the axis near the eyepiece so that the image may be viewed from outside the telescope tube at right angles to the axis.

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Newtonian telescope British  

noun

1. a type of astronomical reflecting telescope in which light is reflected from a large concave mirror, onto a plane mirror, and through a hole in the side of the body of the telescope to form an image

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Etymology

Origin of Newtonian telescope

First recorded in 1755–65

Example Sentences

See Examples For:

Newtonian telescope

This instrument is a Newtonian telescope connected to a UV-sensitive camera.

From Science Daily ● Apr. 21, 2026

After a Pump-room concert I came home Hot-foot, out of the fluttering sea of fans, Coquelicot-ribboned belles and periwigged beaux, To my Newtonian telescope.

From Watchers of the Sky by Noyes, Alfred

In 1774 Herschel has the happiness of being able to examine the heavens with a Newtonian telescope of five English feet focus, entirely made by himself.

From Biographies of Distinguished Scientific Men by Grant, Robert

He has his twenty-foot Newtonian telescope in the open air and mounted in his garden very simply and conveniently.

From Sir William Herschel: His Life and Works by Holden, Edward Singleton

The first was made with a Newtonian telescope something less than seven feet focal length, a power of 222, and an aperture of four and a half inches.

From Sir William Herschel: His Life and Works by Holden, Edward Singleton