Across
- 3. Earth's sister planet
- 6. A layer of gases that surround a planet
- 7. A natural satellite
- 8. Curved path of a celestial object around a larger object
- 10. Relating to Earth
Down
- 1. Closest planet to the sun
- 2. Planets that lie outside the asteroid belt
- 4. Large rounded astronomical body that orbits a star
- 5. Large planets that are mainly made up of gas
- 9. The first four planets from the Sun