Do you ever look up at the stars, sun, or moon and ask endless questions about them? Why do they disappear and reappear every night and day? What about Earth? Does it really move? How do people learn about the planets? How do people even know about more than what’s right around them?

Well, first of all, the planets and stars around us are part of a solar system. All of the planets in our solar system move in an oval shape around the sun (orbit). While they orbit, they also spin (rotate), causing changes in day, night, temperature, and seasons. But how do they not crash into each other? The planets orbit around the sun at different distances, causing them to orbit at different speeds.

The Earth is actually very small compared to the other planets in our solar system. It may seem like because the sun is the biggest, all the planets orbit around it. This is actually not true! Planets orbit around a thing called a barycenter. A barycenter is the little spot between two planets that balances them. Most barycenters are located in or near the sun, making it look like planets orbit solely around it. The sun also has a barycenter, meaning that it also orbits! Bet you didn't know that!

The Earth also moves its axis through a process called precession, which takes millions of years to complete. That's a long time! While the earth is spinning, rotating, and doing circles, it also wobbles and does the wave. This is known as nutation, which proves that the Earth is a pretty good dancer. Last, but not least, the Earth is round, or you could call it a sphere. This seems like something obvious that everyone would know, but you'd be surprised by what the people of the past thought...

A long time ago, people didn't believe that the Earth was round or small, or that it even moved at all. There was the idea that the earth was the center of the solar system, the center of the universe even. This was called the Geocentric model of the solar system, created by a man named Ptolemy and supported by a man named Aristotle.

Over time, everyone came to believe this idea was completely true, and it began to affect civilizations and religions. This new idea fit perfectly with The Church's teachings of humans being the center of everything, which explains why they were very closed off to new ideas about the solar system and Earth.

In later years a man named Galileo created the idea that the sun is the center of the solar system (which is true). This was called the Heliocentric model of the solar system. Galileo spread this idea by writing about it and the teaching it to students. He told everyone who would listen that we live in a solar system that is not focused on religion. This is the exact opposite of what The Church taught and believed. He also came up with the idea of general motion based on what he saw happening again and again. These were big steps forward in science. His ideas were like building blocks in what would become a huge tower when other scientists added their observations and thoughts to it.

As you can imagine, The Church was not happy with Galileo's work because it went against The Church's teachings. They saw Galileo's work as not only disrespectful, but illegal. Galileo was charged with heresy which put him in jail. Because The Church felt Galileo had denied the belief of a baptized member of The Catholic Church and because he shared his ideas with many people, his life of discoveries ended with him dying while under house arrest. Still, he went down in history as being the guy who started the beginning of the scientific revolution with his ideas.