Reflecting telescope for looking at stars

This telescope was called Stargazer. The end is open and looking down, you can see a reflection in  a concave mirror at the bottom. The purple colour is my camera! The mirror focuses the light onto a second mirror and thus into the eyepiece. This version is called a Newtonian Reflector and is the simplest reflecting telescope. The secondary mirror in the middle is a plane mirror. Other versions use convex mirrors and have the eyepiece at the bottom. Using mirrors removes the possibility of chromatic aberration that affects refracting telescope lenses. The edges of the lens act like prisms and split the light up into colours at the edge of the image. But curved mirrors can suffer from spherical aberration unless they are parabolic because spherical mirrors have multiple focal points.