Across
- 3. the force of attraction exted by a mass upon other bodies
- 4. the name given to a collision between two objects
- 8. the name to the system orbiting the sun
- 10. the path of the earth around the sun
- 11. a measurement of time
- 12. our closest star
Down
- 1. a collection of billions of stars
- 2. a round ball shape is called a sphere
- 5. pieces of rock or metal that orbit the sun
- 6. a region in space that has such an enormous force of gravity
- 7. are satellites of planets
- 9. huge spheres of burning gas