Download Discovering Asteroids Using

1. The trail you see behind a meteor as it enters the Earth’s
atmosphere is
ices boiling off its surface due to the heat from the Sun.
b.
turbulence in the air created by the meteor.
c.
gases being ejected from the meteor due to heat from the Sun.
d.
rocky material of the meteor burning up due to friction with the Earth’s
atmosphere.
a.
2. What is a major difference between asteroids and
comets?
a.
b.
c.
d.
Asteroids contain large amounts of ices, whereas comets do not.
Asteroids are mostly located in the outer solar system, whereas comets are mostly
located in the inner solar system.
Comets contain large amounts of ices, whereas asteroids do not.
Asteroids show long tails when they enter the inner solar system, whereas comets
do not.
3. Most meteorite showers originate
from meteors in space whose mutual gravity causes them to form a small
bunch.
b.
from a trail of debris left behind by a comet.
c.
from groups of meteors that have randomly bunched together.
d.
from a very large meteor that was long ago pulverized in a collision.
a.
CHAPTER 9:
Vagabonds of
the Solar
System
WHAT DO YOU THINK?
Are the asteroids a planet that was
somehow destroyed?
! How far apart are the asteroids on
average?
! Why do comets have tails?
! In which direction does a comet’s tail
point?
! What is a shooting star?
!
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You will discover…
discover…
•that asteroids and meteoroids are pieces of
interplanetary rock and metal
•that comets are bodies containing large amounts of
ice and rocky debris
•space debris that fall through the Earth’
Earth’ s atmosphere
•that impacts from space 250 million and 65 million
years ago have affected past life on Earth
Most asteroids
orbit the Sun in
the asteroid
belt between
the orbits of
Mars and
Jupiter.
Relative sizes of the Earth, Moon and
the asteroid Ceres
Asteroids are
classified by their
orbits.
•Belt asteroids
orbit in the asteroid
belt.
•Trojan asteroids
orbit the Sun at
special points in
Jupiter’s orbit.
•Apollo asteroids
have highly
elliptical orbits in
the inner solar
system.
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Discovering Asteroids Using
Time Lapse Photographs
Jupiter’s gravitational attraction produces gaps (Kirkwood gaps) in the asteroid
belt, where the orbital period of the asteroid is a simple fraction of Jupiter’s.
Close-Up Views of Asteroids Show They
Also Have Impact Craters
Asteroid Ida (55 km long)
and its tiny satellite Dactyl
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