A type of reflecting telescope using a concave primary mirror and a flat diagonal secondary mirror.

plural of Newtonian telescope

A telescope in which the medium between the objective and the eyepiece is water instead of air, used in some experiments involving aberration. / A telescope devised for looking into a body of water.

plural of water telescope

An adjustable travelling bag consisting of two cases, the larger slipping over the other.

plural of telescope bag

plural of optical telescope

An instrument, used both for recreational and scientific purposes, which provides a magnified view of distant objects by collecting and focusing light by means of mirrors and/or optical lenses.

plural of Nasmyth telescope

plural of solar telescope