Across
- 3. The planet we live on
- 4. 4.5 billion-year-old yellow dwarf star
- 6. second planet from the Sun
- 8. discovered in 1781 by astronomer William Herschel
- 9. did not meet the three criteria the IAU uses to define a full-sized planet
- 10. Its half the size of Earth
- 11. first planet from the Sun and the smallest planet in the Solar System
- 12. 17 times the mass of Earth
- 13. Belt doughnut-shaped ring of icy objects around the Sun
Down
- 1. the planet with rings
- 2. asteroid belt torus-shaped region in the Solar System
- 5. unit of length
- 7. the largest planet in the solar system