"Since (as I believe) the opinion of Copernicus that Venus revolves about the sun is correct, it is clear that she would necessarily be seen by us sometimes horned and sometimes not, although the said planet is at equal distances from the Sun, at those times, that is, when the smallness of the horns and the effusion of rays do not impede the observations of this difference." (Van Helden, pg. 106.) This is from a letter that Galileo Galilei wrote, that was in his book The Sidereal Messenger, to Benedetto Castelli. This leads into the work, Galileo's Daughter by Dava Sobel, where Galileo's knowledgeable discoveries were not seen as positive as history has shown them to be.
             "If Galileo had attacked some individual thinker for is inadequate arguments in favor of the stability of the earth, we might still put a favorable construction on his test but as he declares war on everybody and regards as mental dwarfs all who are not Pythagorean or Copernican, it is clear enough what he has in mind." (Sobel, Dava pg. 256) This statement by the Jesuit panelist, Melchior Inchofer, shows what Galileo was up against in his day and age. The Copernican idea of the Earth was the center of the universe was believed by most of the people in the world. Galileo had glimpsed the rings of Saturn, which he incorrectly assumed them to verify Saturn's being as three stars in a row, rather than a planet. He then found that Venus, like the moon, went through phases; this provided key evidence for the Heliocentric system, since it recommended that Venus orbited the sun just as the moon orbited the earth. Galileo found the existence of sunspots, by charting them over a period of months, he concluded that the sun actually rotated. All of these observations are evidence for the unbelieved idea of the Heliocentric theory. In Galileo's Daughter it is apparent that the church does not agree with his views on the
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