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General
Copernicus, Nicolaus (1473-1543)
Galileo Galilei (1564-1642)
Einstein, Albert (1879-1955)
Hipparchus (c. 180-125 BC)
Hubble, Edwin P. (1889-1953)
Jansky, Karl (1905-1950)
Kepler, Johannes (1571-1630)
Ptolemy (2nd Century AD)
Shapley, Harlow (1885-1972)
Hawking, Stephen (1942-1998+)

Issac Newton was an English physicist and mathematician who invented calculus, discovered the laws of motion and gravity, layed the foundations of spectroscopy and built the first reflecting telescope

LINKS
Biography of Sir Issac Newton including his work on optics, fluxional method and principia
http://www.geocities.com/Athens/Acropolis/6681/newtonb.htm

A biography of Issac Newton including information on his work and a famous quote
http://scidiv.bcc.ctc.edu/Math/Newton.html

The life of Issac Newton as well as information on his work in optics, the fluxional method and the principia
http://www.newton.cam.ac.uk/newtlife.html

A short account of the history of mathematics with Sir Issac Newton
http://www.maths.tcd.ie/pub/HistMath/People/Newton/RouseBall/RB_Newton.html

Another biography of Sir Issac Newton
http://www.treasure-troves.com/bios/Newton.html