Across
- 3. Aristotle and Ptolemy believed in the _________ model of the solar system.
- 4. He developed an early uniform circular model of motion.
- 9. What analogy do astronomers use to demonstrate the expanding universe?
- 10. What famous astronomer announced that galaxies are moving away from each other in 1929?
- 12. He advanced the theory that the Earth and other planets revolve around the Sun.
- 14. Copernicus and Galileo believed in the __________ model of the solar system.
- 15. The Big Bang happened between ten and ___________ billion years ago. (HINT: spell out the number)
- 17. Who was put on house arrest by the church because he believed in the Heliocentric model?
- 18. In Greek, ______ means Earth.
- 19. The space between galaxies is ________.
Down
- 1. He is thought of as the founder of modern science.
- 2. this is an explanation or model backed by results from many tests.
- 5. What theory is the most accepted universe formation theory?
- 6. In Greek, _______ means Sun.
- 7. Galileo observed what planet went through phases?
- 8. There are _________ of galaxies in the universe.
- 11. The universe includes living things, planets,stars, galaxies, dust clouds,light and even ________.
- 13. He agreed with Aristotle and added mathematics to prove his theory.
- 16. Astronomers say that the galaxies and stars are still moving ________ from each other.
- 18. What force helped galaxies and planets form after the Big Bang?