Space

3. The 4th planet from the Sun
6. A large system of stars held together by their gravity
8. The 5th planet from the Sun
10. A dusty snowball that orbits a star
11. How the Universe was created
12. The 2nd closest planet to the Sun
13. An object orbiting a celestial body of larger mass
15. A small rocky body in space
17. The closest planet to our Sun
19. A group of planets, asteroids, comets and other celestial bodies that orbit around a star

1. The 3rd planet from the Sun
2. A celestial body that orbits a star
4. A natural satellite of a planet
5. The 8th planet from the Sun
7. Where most asteroids are found
9. The 7th planet from the Sun
14. Where most comets are found
16. A celestial body that generates its own light and heat. Consists of a mass of gas held by its own gravity
18. Naturally made object outside the Earth's atmosphere
19. The 6th planet from the Sun