Second Grade Astronomy
One astronomer who showed both imagination and perseverance was Galileo. He faced a lot of opposition when trying to prove and popularize the heliocentric or sun‐centered theory of the universe. Before modern technology was able to prove that the sun was at the center of our solar system and that our universe is made up of many different solar systems, people believed that the earth was at the center. This geocentric model was believed because it was what was easily observable to most people.
When you look up at the sky, you see the sun rise and fall. At night, you see planets and stars, and the moon moving in similar directions as the sun. To a simple observer, it seems that everything is revolving around our planet or planet earth. People did not realize that it was really the earth that moved. This geocentric model was supported by so many people that to say otherwise was considered crazy.
Because Galileo thought differently, he was considered crazy and was punished by society. The majority of people did not want to hear about a sun‐centered universe because it went against what they could see and believe. For a long time scientists and astronomers battled over whether or not the universe was geocentric or heliocentric. As society progressed and science became more conclusive, the heliocentric model of the solar system was proven.
Galileo's Telescope: The Heliocentric Solar System
If you've created your version of Galileo's telescope based on the last book, you can use this telescope to see how Galileo thought that the heliocentric solar system was correct. If you didn't make your own telescope, any telescope should work fine. As you read the following paragraphs, try to compare Galileo's findings to your own sky. You may need to download a star map in order to accurately pinpoint each star and planet correctly.
Galileo was able to prove the heliocentric solar system by simply observing the movements of the planets or stars in the night sky. Using your telescope, begin with Venus. One of the puzzling questions to Galileo was how Venus was able to show different phases of light and dark if it were circling the earth. Through his research and observations, Galileo was able to see that Venus must at some point in its cycle be far away from the earth, and in fact closer to the sun. This gave Galileo an idea that perhaps Venus was orbiting another object.
Fun Facts About Galileo’s Telescope (Second Grade Astronomy continued)
