Across
- 4. 12 people walked on it
- 5. primarily made of gases
- 7. does not have any moon or rings
- 9. densest planet in the solar system
Down
- 1. largest dwarf planet
- 2. reaches temperature of 15 million Celsius
- 3. icy objects on edge of solar system
- 4. way contains black hole in the center
- 6. has a retrograde orbit
- 8. also known as red planet