The document discusses comets and provides key information about their composition, structure, and orbits. It notes that comets are mostly made up of ice and dust, forming tails when close to the sun. Comets can have either long or short orbital periods, with long-period comets originating from the distant Oort Cloud and short-period comets from the Kuiper Belt beyond Neptune. The nucleus and coma are identified as the main parts of a comet. Famous comets mentioned include Halley's Comet and Comets Hale-Bopp and Hyakutake.

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 20th 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.