Across
- 1. the attractive force between objects with mass
- 5. a piece of space dust or rock
- 8. the four closest planets to the sun
- 9. close enough to the earth to give it warmth and light
- 10. a cloud of billions of comets beyond Pluto
Down
- 2. between mars and Jupiter
- 3. dirty snowballs made of dust
- 4. an imaginary line about which a body rotates
- 6. the amount of matter in an object
- 7. when a meteor strikes earth