1. Comets, Asteroids, Meteoroid and Meteorites
What is the difference?

2. Comets
Small body of ice, rock and cosmic dust loosely packed together.
Known as dirty snowballs

4. Comet’s Orbit Orbit the Sun in highly elliptical orbits.
Speed increases as they approach the Sun and slows down as they move to the outer parts of the Solar System.
Comets are dark except when approach sun – reflect sunlight and can be seen
Tail always points away from Sun

6. Parts of a Comet Parts When Near the Sun:
Nucleus: Solid center – ice and dust compacted together
Coma: dense cloud of water, carbon dioxide and other neutral gases
Hydrogen cloud: huge (millions of km in diameter)
Dust tail: up to 10 million km long composed of dust particles driven off the nucleus by escaping gases
Ion tail: as much as several hundred million km long composed of plasma and laced with rays and streamers caused by interactions with the solar wind.

7. The comet's tail gets bigger as it gets closer to the sun and then decreases as it moves away from the sun.

8. Comets Facts Solar winds blow the ion tail away from the sun.
Scientists believe that comets come from the Oort Cloud, a region that surrounds the solar system.
Comets can also come from the Kuiper Belt which exists outside of Neptune’s orbit.
Carry elements of life

9. Asteroids Small, rocky bodies that revolve around the sun.
They range in size from a few meters to more than 900 kilometers in diameter.
Have irregular shapes, but some are spherical, or round.
Most asteroids orbit the sun in asteroid belt between Mars and Jupiter
Asteroids are thought to be left over from the formation of the solar system.

11. Meteoroids, Meteors and Meteorites
Meteoroids are small rocky bodies that travel through space.
A meteor is a bright streak that results from a meteoroid burns up in Earth’s atmosphere, what we call shooting stars.
A meteorite is a meteoroid that reaches the Earth’s surface without burning up.

12. Three Types of Meteorites
Stony- Rocky material
Metallic- Iron and Nickel
Stony Metallic- Rocky material, iron and nickel

13. Stony Meteorites
Rocky material

14. Metallic Meteorite
iron and nickel

15. Stony-Iron Meteorite
rocky material, iron and nickel

16. Meteorite Crater-Winslow, Arizona
This crater was formed approximately 50,000 years ago when an iron mass, estimated to be about 80 feet in diameter and weighing over 60,000 tons entered the Earth's atmosphere over the American Southwest. The resulting formation is about 4,000 feet (1,200 meters) wide and 570 feet (175 meters) deep.

17. A fragment of the meteorite that created Meteorite Crater.
Metallic Meteorite