He was a great Italian astronomer, mathematician, and physicist. By his persistent investigation of natural laws he laid foundations for modern experimental science, and by the construction of astronomical telescopes he greatly enlarged humanity’s vision and conception of the universe. He gave a mathematical formulation to many physical laws.

These sites will get you started. There is lots of information about him on line.

Galileo is the biggest example of “you can’t fight city hall” that I ever saw. Yes, he made countless scientific discoveries, and influenced the way scientific thought would be carried out. To me, though, one of the most compelling facts of his life is that the powers of the day could not stand to be proven wrong, so they snuffed out his findings however possible. Whether he was actually right or not was not the issue to them – the fact that their being proven wrong would undermine their power WAS. I think it’s an inspiring story to see how even though he himself was dominated in the end, his findings still became the “shot heard round the world” that started the dominoes tumbling, leading to a new age of science and reasoning. His example shows me that there’s hope for change, even against seemingly overwhelming opposition, no matter how firmly entrenched. EDIT: Sky, that’s quite a coincidence, us putting essentially the same thoughts in at the same time. I just think my view is slightly different in thinking that the clergy of the time didn’t give the slightest care about God or Earth being the center of the universe at all – they just liked being in power, and Galileo was a threat to it all. Religion ultimately didn’t silence him, it was power-mad bastards who did, citing religion as their authority.

If you click on the links below it will be a good start:

http://www-history.mcs.st-and.ac.uk/Biographies/Galileo.html

http://plato.stanford.edu/entries/galileo/

http://galileo.rice.edu/bio/index.html

http://www.crystalinks.com/galileo.html

http://www.law.umkc.edu/faculty/projects/ftrials/galileo/galileo.html

http://www.bbc.co.uk/history/historic_figures/galilei_galileo.shtml

google his name or go to wikipedia, you will probably find all the information that you want about him.

He invented the telescope, so that’s a start

http://galileo.rice.edu/

http://en.wikipedia.org/wiki/Galileo_Galilei

http://plato.stanford.edu/entries/galileo/

http://www.crystalinks.com/galileo.html