Diary Entry 2

January 7, 1610 

The church don't agree with my beliefs. The inquisitions wishes for me to announce to the world around me that we do not live in a heliocentric universe but instead a geocentric one, under which the Earth is at the centre of our universe. However, I am the wiser. I know that the sun lays at the centre of our universe, and that we on the Earth revolve around it, this heliocentric model is one I shall prove is correct, as Nicholas Capernicus had attempted to before myself. Within this model, the Earth revolves around the sun, which is at the centre of the universe. Mercury, Mars, Venus, Jupiter and Saturn all also revolve around the centred sun. 

Galilei's Heliocentric Model

Today I have made observations which have made my support for this model become even more strengthened. My support of the heliocentric model is brought about due to my observation, study and discovery of the phases of Venus and the moons of Jupiter. The heliocentric model developed by Nicolaus Copernicus predicted that all phases of Venus are visible but due to the fact that the sun is at the centre of the universe. Copernicus however, had no physical evidence, but due to my adaption of the spyglass into a telescope, I am able to study Venus and provide this information. During my observation I discovered that all phases of Venus are visible through an illuminated hemisphere of the planet being visible while it was on the opposite side to the Sun in comparison to our Earth. This illumination of course, being from the Sun. The location of Venus orbiting around the sun would in turn change phases and present different views of Venus. The fact that the phases of Venus are visible not only proves my own beliefs but sheds light upon the validity of the heliocentric model.

The Phases of Venus (Galileo's Findings)

                                                       The Phases of Venus Video

Also, through the use of my newly invented telescope I was able to discover 3 objects which I believe to be orbiting Jupiter, much like my heliocentric belief that the moon orbits our Earth. These 3 objects then turned into 4, and I came into realisation that these objects are moons, and they do orbit Jupiter. I shall name the moons; Io, Europa, Ganymede, and Callisto, after the Medicis. My discovery, has lead to Copernicus's heliocentric model to be the only accurate one in the view of pure science, as the geocentric model states that the Earth and it's moon are not in orbit and if these celestial objects were in orbit the moon would be separated from the Earth. However, through study the changed in positions in the Moon's of Jupiter I am able to prove that moon's do orbit and will come around on a regular and predictable cycle. Thus, the heliocentric model is growing ever more supported. 

Jupiter's Moons as seen by Galileo

                                                                         

Jupiter's Moons and Their Galilean Names

After finding this evidence supporting the Heliocentric model, and with little more research to be done due to my only resource being a low magnifying telescope, I will end my Astronomical Career with the knowledge that I may have very much proved the Heliocentric model put forth by Copernicus, and as he stated “Finally we shall place the Sun himself at the center of the Universe.