The solar system

5. Most of what astronomers know about mercury has come from
6. Axis of rotation is tilted at an angle of about 90 degrees
9. Trapping of heat by the atmosphere is called the
11. Meteoroids that pass through the atmosphere and are found on Earth’s surface are called
12. Region beyond the kuiper belt stretches out more than 1,000 times the distance between the sun and Neptune
14. Clouds of gas and dust that form a fuzzy outer layer on a comet's heaad
16. The largest planet that revolves around the sun
19. The inner planets are often called the
21. Jupiter's largest moon
22. A thin disk of small particles of ice and rock
23. Its atmosphere contains visible clouds

1. A giant impact almost broke this moon apart
2. Region beyond Neptune's orbit that extends to about 100 time Earth's distance from the sun
3. The region of the solar system between Mars and Jupiter
4. The solid inner core of a comet
7. Are chunks of rock or dust smaller than asteroids
8. Atmosphere is so heavy and thick that would crush a human
10. Called the red planet
11. Has no atmosphere
13. 70% is covered with water
15. Loose collections of ice, dust and small rocky particles
17. A dwarf planet that orbits around Neptune
18. Jupier, Saturn, Uranus and Neptune are...
20. Meteoroid enters Earth’s atmosphere, friction with the air creates heat and produces a streak of light known as a