Which telescope type is classified as a reflecting telescope?

A reflecting telescope is one that uses mirrors to gather and focus light. This type of telescope typically includes a concave primary mirror that reflects light to a focal point and often has a smaller flat secondary mirror that directs the light to an eyepiece or camera. The primary advantage of reflecting telescopes is that they can be built much larger than refracting telescopes without the issues of chromatic aberration, allowing for clearer images of distant celestial objects.

In contrast, the Galilean and Keplerian telescopes are both types of refracting telescopes, which utilize lenses to focus light instead of mirrors. The Galilean telescope, developed by Galileo, uses a convex objective lens and a concave eyepiece, while the Keplerian telescope features two convex lenses. Newcastle does not denote a well-known type of telescope within the typical classifications used in astronomy.

Thus, the classification of a telescope as a reflecting telescope specifically refers to those utilizing mirrors, correctly identifying it as the answer.