Across
- 1. the time it takes the Earth to complete a rotation on its axis
- 5. a cloud of gas and dust in space
- 8. furthest known planet in our Solar System
- 10. the group of planets which includes Jupiter, Saturn, Uranus, and Neptune
- 11. an envelope of gases surrounding the Earth or another planet
- 12. the path in space followed by a celestial body
- 13. the region of space which separates the terrestrial and Jovian planets
- 14. the extreme upper region of an atmosphere in which the motion of the gas is controlled by the planet's magnetic field
- 15. used to be a planet, now a dwarf planet
- 16. a region of space past Neptune extending to roughly 1000 AU and the source of comets with periods less than 200 years
- 19. a small body in orbit around the Sun, consisting of a tiny, icy core and a tail which forms when close to the Sun
- 22. third rock from the Sun
- 23. a small, generally rocky, solid body orbiting the Sun
- 25. a planet known for its rings
- 26. a circular pit, generally with a raised rim, often formed by the impact of an asteroid
- 27. this in combination with the revolution of the Earth around the Sun results in the seasons
Down
- 2. the time it takes the Earth to complete a revolution around the Sun
- 3. the largest planet in our Solar System
- 4. the Earth's "twin" in mass and diameter, it rotates clockwise, and you wouldn't want to live there
- 6. the blockage of light from one space object caused by the passage of another between it and the observer
- 7. a natural satellite of a planet
- 9. Mercury, Venus, Earth, and Mars are this type of planet
- 14. approximately the time it takes the Moon to complete a rotation on its axis
- 17. a planet with an extreme tilt
- 18. a body in orbit around a star which has cleared its orbit and has enough gravity to achieve a rounded shape
- 20. the planet closest to the Sun
- 21. often called the "red planet"
- 24. the cloud beyond the Kuiper Belt from which comets with periods greater than 200 years originate