Across
- 3. The natural satellite of the earth (other planets have them too).
- 5. The sun is composed of hydrogen and __.
- 8. Sphere-shaped group of small rock and ice that are the furthest objects from the sun.
- 10. The third planet from the sun.
- 12. The closest planet to the sun
- 13. The farthest planet from the sun
- 14. Debris from comets that would be meteors if they enter earth's atmosphere.
- 15. These orbit the sun and are located between Mars and Jupiter.
- 17. When an object spins on its axis
- 19. Disk-shaped group of small rock and ice beyond the orbit of Neptune.
- 21. Force of attraction between two objects due to their masses.
Down
- 1. The process in which plants create oxygen and chemical energy, which is one reason why life exists on earth.
- 2. The earth is 78% __.
- 3. These burn when entering the atmosphere, causing light.
- 4. Jupiter, Saturn, Uranus, and Neptune are all __ planets.
- 6. The earth is 21% __.
- 7. These form large tails of gas and dust, melt when they near the sun, and originate from the Kuiper belt or Oort cloud.
- 9. The largest and hottest object in our solar system.
- 11. When an object moves around another object.
- 16. the curved path of a celestial object or spacecraft around a star, planet, or moon
- 18. Mercury, venus, earth, and mars are all __ planets.
- 20. The collection of planets, moons, and other objects that orbit around the sun.