Galileo's refractor (1609)

Newton's reflecting telescope (1668)

Yerkes refractor (1895).

Mount Wilson 60-inch telescope (1908).

Hooker 100-inch telescope (1917).

Hale 200-inch telescope (1948).

Horn Antenna (1959).

Very Large Array (1980).

Hubble Space Telescope (1990).

Keck telescopes (1993 and 1996).

Sloan 2.5-m telescope (1998).

WMAP (2001).

Swift (2004).