Primary Mirror

A primary mirror (or primary) is the principal light-gathering surface (the objective) of a reflecting telescope.

Read more about Primary Mirror:  Description, Superlative Primary Mirrors

Famous quotes containing the words primary and/or mirror:

    “At the heart of the educational process lies the child. No advances in policy, no acquisition of new equipment have their desired effect unless they are in harmony with the child, unless they are fundamentally acceptable to him.”
    —Central Advisory Council for Education. Children and Their Primary Schools (Plowden Report)

    “There is a small steam engine in his brain which not only sets the cerebral mass in motion, but keeps the owner in hot water.”
    —Unknown. New York Weekly Mirror (July 5, 1845)