What information did Galileo have that the Ancient Greeks didnt?

I need help with my science homework - one of the tasks is to: Explain why the ancient Greeks has not been able to use the same information as Galileo when they drew their model of the solar system. HELP!What information did Galileo have that the Ancient Greeks didnt?telescope
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which specifically showed him the phases of VenusWhat information did Galileo have that the Ancient Greeks didnt?Copernicus came before Galileo and he was the first to realize that the sun and stars did not cirle the earth. Galileo invented the telescope and he agreed after realizing that all planets were ROUND like the sun and the moon. He figured the earth must be round like a ball and then compared the shadows on the ground at different places on earth at the same time of year meant the earth had to be round like a ball. Then Newton realized that gravity made these objects round.What information did Galileo have that the Ancient Greeks didnt?Guts...thats what Galileo had..

His renowned conflict with the Catholic Church was central to his philosophy, for Galileo was one of the first to argue that man could hope to understand how the world works, and, moreover, that we could do this by observing the real world.

Galileo remained a faithful Catholic, but his belief in the independence of science had not been crushed. Four years before his death in 1642, while he was still under house arrest, the manuscript of his second major book was smuggled to a publisher in Holland. It was this work, referred to as Two New Sciences, even more than his support for Copernicus, that was to be the genesis of modern physics.