Your Friend, a Graduate Student in Astronomy, Is Giving You

Multiple Choice

Your friend, a graduate student in astronomy, is giving you a special tour of the local observatory. You notice that you are viewing the image from the big telescope from underneath the primary mirror; the beam of light has come through a small hole in the main mirror to an eyepiece below. This telescope uses what focusing arrangement?

A) prime focus
B) Newtonian focus
C) Cassegrain focus
D) Galilean focus
E) out of focus