Across
- 2. When something is not moving
- 4. A substance that a wave passes through
- 6. Places in space so strong not even light can escape
- 7. A white dwarf that has been cooled down in temperature
- 8. A speeding-up change in speed
- 9. The way an object is going
Down
- 1. A push, pull or twist
- 3. The start of a star
- 5. A slowing down in speed