TOPIC 11 Lesson 1

3. Astronomer whose model placed Earth at the center
8. A Sun-centered model of the solar system
10. An object that revolves around another object in space
11. The star that appears nearly stationary above Earth's North Pole
13. Scientific observations used to support or challenge a model
15. Scientist who used a telescope to gather evidence supporting the heliocentric model
16. Astronomer known for making careful observations of planetary motion
17. The shape of a planet's orbit around the Sun
18. Ancient Greek scientist who proposed an early Sun-centered model
20. Scientist who explained that Earth rotates and revolves around the Sun

1. A large spherical object that revolves around a star
2. A scientist who studies stars, planets, and other objects in space
4. An instrument that makes distant objects easier to observe
5. A representation scientists use to explain or predict how a system works
6. The path an object follows as it revolves around another object
7. An Earth-centered model of the solar system
9. A recognizable pattern or group of stars as seen from Earth
12. Earth's spinning motion that makes stars appear to move across the night sky
14. Scientist who determined that planets travel in elliptical orbits
19. An object in space that produces its own light and energy