Galileo's finding that Venus goes through these, like the moon, was the 1st direct evidence for Copernican ideas
He found that the surface of the Moon was irregular and not smooth, as had ... 
of his findings with the telescope, he left in the summer of 1610 to become "first... [DOC] [TLE] Chapter 2, Section 5 [PAR] By being willing to perform experiments to test his ideasa rather radical ...