Comets

Comet Presentation for Grade 8

1. NEO (Near-Earth Objects) Comets and Asteroids

2. COMETS

3. Comets

4. Comet Humans have observed comets since prehistoric times. Comets were long regarded as supernatural warnings of calamity or signs of important events .

5. Comet of 1577

6. Bayeaux Tapestry Norman Invasion of 1066

7. Comet This distinctive visible tail is the origin of the word comet , which comes from Greek word KOMETES meaning “long-haired star.”

8. Key Concepts Comets are mostly made of dirt and ice. Comets are often called dirty snowballs or icy mud balls. A comet develops a tail when it gets close to the Sun. A comet’s tail always points away from the Sun.

9. Key Concepts Meteor showers are caused when Earth moves through the debris left behind by comets. Comets move in elliptical orbits with random orientations. Most comets come from the Oort cloud at the outer edges of the solar system.

10. Key Concepts Long-period comets come from the Oort Clouds. (located beyond Pluto; take 200 to million years to complete their orbit around the sun)

11. Key Concepts Short-period comets come from the Kuiper Belt. ( located beyond Neptune; take 75-79 years to complete their orbit around the sun)

12. Parts of a Comet

13. Parts of a Comet 1. Coma - luminous cloud of gas and dust surrounding the head of a comet . 2. Nucleus - the central core in the head of a comet, consisting of ice, frozen gases, and dust . 3. Ion/Plasma Tail 4. Dust Tail

14. Famous Comets Comet Halley (1P/Halley) – named after Edmund Halley. This is the most famous comet of the 20 th century.

15. Self-Check Halley’s comet appeared in the night sky in 1910 and then again in 1986. When will it appear again? In 2061-2062

16. Famous Comets Comet Hale-Bopp

17. Famous Comets Comet Hyakutake reached the closest point to earth in its path through the inner solar system on March 25, 1996. A ball of dust and ice, the comet was bright enough to be seen with the naked eye.

18. Assignment Make a research about at least five (5) comets.