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:

    “A fact is a proposition of which the verification by an appeal to the primary sources of our knowledge or to experience is direct and simple. A theory, on the other hand, if true, has all the characteristics of a fact except that its verification is possible only by indirect, remote, and difficult means.”
    —Chauncey Wright (1830–1875)

    “A man’s memory is bound to be a distortion of his past in accordance with his present interests, and the most faithful autobiography is likely to mirror less what a man was than what he has become.”
    —Fawn M. Brodie (1915–1981)