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:

    Europe has a set of primary interests, which to us have none, or a very remote relation. Hence she must be engaged in frequent controversies, the causes of which are essentially foreign to our concerns. Hence, therefore, it must be unwise in us to implicate ourselves, by artificial ties, in the ordinary vicissitudes of her politics or the ordinary combinations and collisions of her friendships or enmities.
    George Washington (1732–1799)

    Looking at yourself in a mirror isn’t exactly a study of life.
    Lauren Bacall (b. 1924)