It was the prototype for a design that later came to be called a newtonian telescope.

This type of telescope is still called a Newtonian telescope.

The design uses a 45 flat secondary mirror to view the image, as in a standard Newtonian telescope.

The Newtonian telescope's simple design makes them very popular with amateur telescope makers.

At that time, the observatory consisted of a dome housing a 41cm Newtonian telescope and small library.

Later on such prototype for a design came to be called a Newtonian telescope or Newton's reflector.

Whereas an 8-inch Newtonian telescope would have been considered large 30 years ago, today 16-inch systems are common, and huge 32-inch systems not all that rare.

In 1721 he showed the first parabolic Newtonian telescope to the Royal Society.

A telescope with only one curved mirror, such as a Newtonian telescope, will always have aberrations.

With John and his brother, Henry, George had constructed effective Newtonian telescopes.

There are modern commercial and amateur mount designs for Newtonian telescopes that have the "ball" built into the base of the optical tube assembly.

Isaac Newton 1668 builds the first reflecting telescope, his Newtonian telescope.

The first Newtonian telescope was mounted in this way; the ball was held in place by wrought iron springs.

Jack helped establish the astronomy program at "Pearson College", and donated his 25-inch Newtonian telescope to it.

Newtonian telescopes are usually less expensive for any given objective diameter (or aperture) than comparable quality telescopes of other types.

They became interested in the Mills Observatory's Newtonian telescope as its mounting appeared ideally suited for their purpose.

The main instrument at Sherwood Observatory is a Newtonian telescope on an equatorial fork mount.

Schmidt-Newtonian telescopes offer images with less coma than Newtonian telescopes of the same focal ratio (usually about half).

Coleg Trefeca still displays a Newtonian telescope which Joseph is said to have made himself and to have used for the observations.

The Lurie-Houghton uses a spheroidal primary mirror unlike the paraboidal mirror used in the Newtonian telescope.

The secondary mirror in the Lurie-Houghton is comparable to the secondary mirror in a Newtonian telescope.

In astronomy, the Arago spot can be also easily observed in the strongly defocussed image of a star in a Newtonian telescope.

Isaac Newton knew about the properties of parabolic mirrors but chose a spherical shape for his Newtonian telescope mirror to simplify construction.

The club continued expanding in 1979 and a 12.5" Cave Newtonian Telescope was installed in a roll-off observatory onsite.

A Newtonian telescope is a type of telescope that was invented by the English scientist Sir Isaac Newton.