1. Comets, Meteors, and Asteroids

2. Structure of a Comet To Sun Ion Tail Dust Tail Coma

3. Comet Structure  Nucleus  10 km “Dirty Snowball”  Coma  Cloud of evaporated ices and ions  may be 100,000 km in diameter  Tail  Always points away from Sun  Solar Wind and Radiation Pressure

4. The Oort Cloud  In 1950 Jan Oort noticed that  no comet has been observed with an orbit that indicates that it came from interstellar space,  there is a strong tendency for aphelia of long period comet orbits to lie at a distance of about 50,000 AU, and  there is no preferential direction from which comets come.

5. The Oort Cloud

6. Comet Halley

7. Bayeaux Tapestry Norman Invasion of 1066

8. Comet Halley 1910 Pope Callixtus III excommunicated Halley's Comet in 1456 In 1910, charlatans sold "comet pills" Orbit

9. Comet Nucleus

10. Comet of 1577

11. Hyakutake

12. Hale-Bopp

13. Comet West

14. The Cause of Meteor Showers P55/Tempel-Tuttle

15. Why After Midnight is Best Rotational Velocity Orbital Velocity Midnight

16. Shower Radiant

17. The 1833 storm

18. The 1966 storm

19. 1997 Leonids from Orbit

20. Two Showers for Halley

21. Sporadic Meteors IronsStony-Irons Chondrites Carbonaceous Chondrite Achondrite

22. Barringer’s Crater An iron meteorite 100 feet across and 70,000 tons slamed into the Earth at about 43,000mph in the Arizona desert near Flagstaff 40,000 years ago. Barringer Crater is 4,100 feet wide and 571 feet deep.

23. Other Impact Craters

24. Tunguska, 1908

25. How Much Damage?

26. Ida - Dactyl

27. Gaspra

28. Kirkwood Gaps

30. End of Section