Our Solar System
Planets and other
objects form a system
around our Sun.
Key Concepts
SECTION
1
Planets orbit the Sun
at different distances.
Learn about the sizes and
the distances of objects in
the solar system and about
its formation.
SECTION
2
The inner solar system
has rocky planets.
Learn about the processes
that shape Earth and
other planets.
SECTION
3
The outer solar system
has four giant planets.
Learn about the largest
planets.
SECTION
4
Small objects are made
of ice and rock.
Learn about moons, asteroids,
and comets.
Prepare and practice for
the FCAT
• Section Reviews, pp. 747,
756, 763, 769
• Chapter Review, pp. 772–774
• FCAT Practice, p. 775
CLASSZONE.COM
• Florida Review: Content
Review and FCAT Practice
740 Unit 6: Space Science
This image shows
Jupiter with one of
its large moons. How
big are these objects
compared with Earth?
How Big Is Jupiter?
Measure 1.4 mL of water (about
22 drops) into an empty 2 L bottle
to represent Earth. Use a full 2 L
bottle to represent Jupiter.
Lift each one.
Observe and Think How
big is Jupiter compared with
Earth? Using this scale, you
would need more than
nine hundred 2 L bottles
to represent the Sun. How big is
the Sun compared with Jupiter?
How Round Is an Orbit?
Tie a loop 10 cm long in a piece of string.
Place two thumbtacks 2 cm apart in the center
of a piece of paper. Loop the string around
the thumbtacks and use a pencil to draw
an oval the shape of Pluto’s orbit.
Remove one thumbtack.
The remaining thumbtack
represents the Sun.
Observe and Think How
would you describe the shape
of this orbit? How different is
it from a circle?
Internet Activity: Spacing
Go to ClassZone.com to take a virtual spaceflight
through the solar system. Examine distances
between planets as your
virtual spaceship travels
at a constant speed.
ClassZone.com
Back
Location:
Forward
Reload
Home
Images
Print
Security
Stop
http://www.classzone.com
Observe and Think
What do you notice about
the relative distances of
the planets?
NSTA
scilinks.org
The Solar System Code: MDL059
Chapter 21: Our Solar System 741
CHAPTER 21
CONCEPT REVIEW
VOCABULARY REVIEW
• The planets we see are
much closer than the stars
in constellations.
orbit p. 674
solar system p. 674
satellite p. 687
• The Sun, the planets, and
smaller bodies make up the
solar system.
impact crater p. 696
axis of rotation p. 708
• Scientists observe different
types of electromagnetic radiation from space objects.
FLORIDA REVIEW
CLASSZONE.COM
Content Review and FCAT Practice
TAKING NOTES
MAIN IDEA
AND DETAILS
Make a two-column chart.
Write main ideas, such as
those in the blue headings, in the column on the
left. Write details about
each of those main ideas
in the column on the right.
VOCABULARY
STRATEGY
Draw a word triangle
diagram for each new
vocabulary term. In the
bottom row write and
define the term. In the
middle row, use the term
correctly in a sentence.
At the top, draw a small
picture to help you
remember the term.
742 Unit 6: Space Science
MAIN IDEAS
DETAIL NOTES
1. Planets have different
sizes and distances.
1. Objects in the solar system
• Sun
• planets
• moons
• comets and asteroids
2.
2.
AU
Jupiter is
about 5 AU from
the Sun.
astronomical unit (AU):
Earth’s average distance
from the Sun