1. Asteroids
Cristal Locke
Catch a falling star!

2. Asteroid Pre-Test The asteroid belt is between which 2 planets?
Are all the asteroids in the asteroid belt?
Are asteroids bigger or smaller than planets?
What are asteroids made of?
What is the name of the first asteroid found?

3. Asteroids Rocky or metallic objects.
Most orbit the Sun in the asteroid belt.
Asteroid belt is between Mars and Jupiter.

4. They are big!
Asteroids are large. They are sometimes called minor planets.

5. Comic Relief

6. Will it crash?
It takes 3 – 6 Earth years for an asteroid to orbit around the sun.
Jupiter’s gravitational force keeps the asteroids from crashing into the inner planets.

7. Kirkwood Gaps
The belt is not smooth. There are gaps (holes) in the belt.
These gaps are called Kirkwood Gaps.

8. How many? 40,000 known asteroids
The first one discovered was named Ceres. It was discovered in It’s also the largest asteroid discovered.

9. Asteroid or Moon?
Asteroids can be pulled out of their orbit and orbit a planet instead of the sun.
Phobos and Deimos (Mars moons) may have once been asteroids.

10. Interactive Puzzle

11. Asteroid Clay Make your own asteroid from clay.
Make sure your asteroid has a distinct shape, bumps, and a cratering pattern.
Pictures will be taken of your asteroid.
You will later identify your asteroid.

12. Comets
Cristal Locke

13. Comet Pretest What is the nucleus of a comet made of?
Name a well-known comet whose visit was recorded in ancient times?
Does a comet's tail ever face the Sun?
What is the name of a comet that crashes into the sun (or gets so close that it burns up)?

14. Label the Comet

15. Comets
A comet is a small icy body that orbits around the sun.

16. It is made up of: a nucleus – solid, frozen ice, gas and dust
a gaseous coma – water vapor, CO2, and other gases
a long tail – made of dust and ionized gases

17. Comet Tail
Its long tail always points away from the sun because of the force of the solar wind (a continuous stream of ions (electrically charged particles) that are given off by the sun)
The tail can be up to 250 million km long, and is most of what we see.

18. Label the Comet

19. Comet Parts Coma – blob of gas that surrounds the nucleus of a comet
Dust Tail – long, wide tail that curves because of the comet’s motion
Hydrogen Envelope – hydrogen gas that surrounds the coma and trails for millions of miles

20. Comet Parts
Ion Tail – tail of charged gas particles (ions) that always face away from the sun
Nucleus – frozen center of the comet’s head

21. Comet’s Orbit

23. Comet Exploration
NASA's Student Mission will visit the Comet Wild 2 in 2004.
It will take a sample of comet particles and return them to Earth.
The small spacecraft (about 770 pounds = 350 kg) was launched February 7, 1999 and will rendezvous with comet Wild 2 in January, 2004.
It will return to Earth on January 15, 2006, and land in western Utah, USA.

24. Sungrazers
Some comets crash into the Sun or get so close that they burn up; these comets are called sungrazers.

25. Haley’s Comet Haley's comet is earliest-recorded sighting was
It was recorded in 240 B.C. in China
Edmund Halley was the first person to recognize that it was periodic.
It was last seen in 1986 and will be seen next in the year 2061; its period is 76 years.

26. Popular Comets A Few Comets Discovered Last Visit Next Visit
Period (Years)
Biela
1772
1852
Broken Up
6.62
Encke
1786
2000
12/23/03
3.28
Faye
1843
1999
2006
7.34
Hale-Bopp
7/23/95
1997
4377
2380
Halley
240 BC
1986
2061 76
Hyakutake
1/30/96
1996
31,496
29,500
Kohoutek
3/7/73
1973
76,973
75,000

27. Hale-Bopp Comet

28. Make a Comet