Across
- 3. A very bright object that's similar to star and far away in space
- 4. an act of counting numbers in reverse order to zero
- 6. The explosion of a star
- 8. a system of stars held together by gravitational attraction
- 9. The largest planet in the solar system
Down
- 1. Another word for'The Earth'
- 2. the region beyond Earth's atmosphere
- 5. the seventh planet from the sun
- 6. A fixed luminous point in the night sky
- 7. A celestial body moving in an elliptical orbit around a sun