1. OTHER OBJECTS
IN SPACE

2. ASTEROIDS Very small irregularly shaped, rocky bodies Orbit the Sun
No atmosphere or internal heat
Can hit a planet if it gets close enough to be pulled in by gravity

3. ASTEROID BELT Hundreds of thousands located there
Mostly located between Mars and Jupiter
Formed at same time as rest of solar system
Jupiter’s massive gravity kept them apart

4. NEAR-EARTH ASTEROIDS Have orbits that cross Earth’s orbit
Over 4,500 known to pass near
Earths atmosphere
Large asteroids in Earth’s past have
caused mass extinction
of organisms

5. METEOROIDS Debris left behind by comets and asteroids
Large as boulders called asteroids
Small as tiny grains of sand called interplanetary dust
Sometimes cluster together with long tails

6. METEORS Forms a streak of light across the sky
Often called shooting stars
Light from burning meteor
as it flies through Earth’s
atmosphere
Can come from comets,
asteroids, or meteoroids

7. METEORITES Meteor that does not completely burn up in the atmosphere
Provide clues about our solar
system
Some from asteroids or comets
Some are from nearby bodies
like Mars

8. METEORIODS, METEORS, AND METEORITES Meteoroid is dragged toward
Earth by gravity
It enters the atmosphere
Friction heats the object
As it flies in Earths atmosphere
it leaves a trail of glowing
gases it is now a meteor
Most meteors never reach Earth
Small core remains and hits
Earth it is called a meteorite

9. COMETS Small icy objects that orbit the Sun Highly elliptical orbits
Close to sun outer layers of ice melt
Vaporized gas and dust form a “coma”
Gases in coma and tail reflect light
from sun
Comets disappear when they move
away from the sun
Comet’s period is length of time from
one visit close to Earth and the next

10. COMETS Where do they come from?
Short period comets – 200 years or less
come from the Kuiper belt – a
region beyond Neptune
Long period comets – thousands or
millions of years come from a
very distant region of the solar
system –Oort cloud
Comets may have brought water into
the early Earth

11. DWARF PLANETS Objects that have not cleared their
orbits of smaller objects
Not enough gravity to clear objects
Five dwarf planets in our solar system
Ceres
Pluto
Makemake
Haumea
Eris