Astronomy Vocabulary

3. Sunlight striking dust grains that impart a tiny force to the dust tail
8. Contain traces of radioactive material that can be used to determine age
9. When breakup occurs
10. A swarm of trillions of icy bodiesthat lie far beyond the orbit of Neptune
11. Happens when a force that acts repeatedly on a body constantly re-inforces the body's motion
13. All grains move in the same direction, away from the Sun
14. Larger peices that manage to get to the ground
16. Pass in front of
18. Rocky or metallic bodies that can sometimes be considered dwarf planets
19. A flow of ions that streams from the Sun into space
22. Small, Planet like bodies
23. Planets that are gaseous and liquid
25. Produced when light at one wavelength is converted to light at another wavelength

1. Usually a blue-ish color and points directly away from the Sun
2. A long, narrow column of dust and gas
4. Planets orbiting stars other than the sun
5. Seemingly empty regions in the asteroid belt
6. Meteorites that have a lumpy structure
7. A cloud of gas of which the tail emerges
12. A region between the orbits of Mars and Jupiter
15. A solid body, while in space and before it reaches the atmosphere
17. Stony meteorties that dont have chondrules
20. Planets that are small rocky bodies with relatively thin or no atmospheres
21. A glowing trail of hot gas and vaporized debris left by a solid object heated by frictionas it moves through Earth's atmosphere at extremely high speed
24. Steep cliffs that run for hundreds of kilometers across Mercury's surface