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Galileo and parallax measurements.
While teaching at the University of Padua, Galileo delivers lectures about the new star that was discovered. He claims that parallax measurement put the star beyond the moon. This further proves there must be change in the heavens. -
Galileo makes his own telescope
Galileo hears about the invention of a device that lets you view things far away as if they were close by. He then duplicated the design and made his own telescope. -
Galileo first makes observations of the sky
Galileo was the first one to make systematic observations of the sky through his telescope. He was trying to answer the question of Earth's placement. -
He studies the moon
Galileo was the first one to discover the moon was not perfect. He discovered mountains and craters, he used the shadows on the mountains to calculate the height of some of them. This clashed the Ptolemaic model that the moon was in the heavens. -
Galileo observes the Milky Way through his telescope.
Galileo dicovered that the Milky Way was actually made up of lots of stars that were to faint to see with the unaided eye. -
Galilean Moons
Galileo observerd three stars near Jupiter which he originally thought were planets. He later learned that these were moons orbiting Jupiter. This further disproved the geocentric model of the universe. -
Galileo discovers Ganymede
Galileo discovered Ganymede, Jupiter's largest moon, shortly after the others. This supported the Copernican model over the Ptolemaic model. -
Saturn's rings
Galileo observes Saturn and thought that the rings were three stars almost touching each other. He later observed Saturn and saw that the "stars" had disappeared. -
The phases of Venus
Galileo discovered that Venus goes through phases like the moon. This proved that Venus revolves around the sun, like the Earth. -
Galileo discovers sunspots
He was the first to observe sunspots. This showed that the sun was not perfect and further disproved the idea that the heavens were perfect. -
Galileo proved the sun was a sphere
Galileo noted that the sunspots were moving, and this led him to the conclusion that the sun was a sphere rotating on an axis. -
Galileo observes Neptune
When Galileo first observed Neptune he originally thought it was a fixed star, due to his telescope not being powerful enough to let him see that far. -
Galileo provides explanation for earthshine
Galileo provided an explanation that the reason the Moon's dark side glowed some days was due to reflected light from the sun coming off Earth's surface. -
Galileo's theory on tides
Galileo wrote his theory on tides. He wrote that the tides move along with the Earth. -
Dialogue on the Two Chief World Systems
Galileo publishes a book bout the theory of the heliocentric universe and the geocentric universe. He favors the heliocentric theory and this angerd the pope and lead to Galileo's imprisonment.
