Meaning of Gregorian telescope | Babel Free

Definitions

A type of reflecting telescope having two concave mirrors: the primary mirror (a paraboloid) collects the light and brings it to a focus before the secondary mirror (a ellipsoid), where it is reflected back through a hole in the centre of the primary, and thence out the bottom end of the instrument, where it can be viewed with the aid of the eyepiece.

CEFR level