The Phases of Venus - A Heliocentric Revoultion

One of the most convincing arguments Galileo had in the battle for heliocentrism dominance was his observance of the phases of the planet Venus. I will be focusing on this aspect of Galileo's life for our collaborative effort, because I believe Venus's phases were one of Galileo's most powerful weapons in the system war.

The phases of Venus were first observed by Galileo in 1610 using a telescope of his invention. These phases are essentially the same thing as the phases of the moon, in that their phases are dependent on their positions relative to the Sun. This hypothesis, however, clashed with the Ptolemaic system, which has the Earth as the center of the solar system. This is because the Ptolemaic system has the Sun in an orbit behind Venus, (between the Earth and the Sun) meaning that Venus could never be fully lit.

This finding made a strong argument for a heliocentric system, and is therefore an important aspect of Galileo's life. As far as my contribution is concerned, a very crucial part of explaining Galileo's discovery would be to include an image comparing the two systems, a good example of which is shown at the bottom of this blog. However, it is important to cut down on the jargon, give the date and some details, and let the image do most of the explanation work. This idea gives a strong reference point between the two systems, and does a good job of contrasting the two systems in easily understood terms. The scientific implications of this discovery would resonate with "scientists" (natural philosophers) to come, leaving the door open for men such as Issac Newton.

Conclusively, I will be doing my two-page spread over the phases of Venus using a picture of the phases, approximately 100-150 words to describe what Galileo saw and how he observed the phases, the implications of this discovery, and perhaps a picture of Galileo gazing at the Heavens.