(NB. Blue links are links within the current page. Purple links are external links to other web sites. Pale Green links are are to other pages at this site.)
General
Copernicus, Nicolaus (1473-1543)
Galileo Galilei (1564-1642)
Einstein, Albert (1879-1955)
Hipparchus (c. 180-125 BC)
Jansky, Karl (1905-1950)
Kepler, Johannes (1571-1630)
Newton, Issac (1642-1727)
Ptolemy (2nd Century AD)
Shapley, Harlow (1885-1972)
Hawking, Stephen (1942-1998+)

Edwin Powell Hubble revolutionised our knowledge of the size, structure and properties of the universe by using the largest telescope of his time. He proved that galaxies are small 'universes' and created a system to classify them by. Today, there is a large telescope in orbit named after him.

LINKS
Information on his work and a short biography
http://www.ciw.edu/Hubble.html

A short biography of Hubble
http://www.phys-astro.sonoma.edu/BruceMedalists/Hubble

Plain text biography of Hubble
http://www.nor.com.au/users/gaiaguys/hubble.htm

Complete Biography of Edwin Hubble
http://antwrp.gsfc.nasa.gov/diamond_jubilee/hubble_nas.html

All the information you could want to know about the Hubble Telescope...including diagrams, pictures, links to NASA and equations etc.
http://www.pbs.org/deepspace/hubble/index.html

Hubble's galaxy classification system with diagrams
http://zebu.uoregon.edu/~js/ast123/lectures/lec13.html