Students know telescopes magnify the appearance of some distant objects in the sky, including the Moon and the planets.. Students know that Earth is one of several planets that orbit t
Trang 1Genre Comprehension Skill Text Features Science Content
Nonfi ction Predict • Captions
• Diagrams
• Labels
• Glossary
Objects in Space
Scott Foresman Science 3.6
Standards Preview
Standard Set 4 Earth Sciences
4 Objects in the sky move in regular
and predictable patterns As a basis
for understanding this concept:
4.a Students know the patterns
of stars stay the same, although
they appear to move across the sky
nightly, and different stars can be
seen in different seasons.
4.c Students know telescopes magnify
the appearance of some distant objects in the sky, including the Moon and the planets The number of stars that can be seen through a telescope is dramatically greater than the number that can be seen by the unaided eye.
4.d Students know that Earth is one of
several planets that orbit the Sun and that the Moon orbits Earth.
ISBN 0-328-23533-4
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Earth Sciences
by Peggy Bresnick Kendler
Trang 2asteroid
binoculars
orbit
planet
solar system
star
telescope
Picture Credits
Every effort has been made to secure permission and provide appropriate credit for photographic material The
publisher deeply regrets any omission and pledges to correct errors called to its attention in subsequent editions.
Unless otherwise acknowledged, all photographs are the property of Scott Foresman, a division of Pearson Education.
Photo locators denoted as follows: Top (T), Center (C), Bottom (B), Left (L), Right (R), Background (Bkgd)
Opener ©Earth Imaging/Getty Images; 2 ©Photographer’s Choice/Getty Images; 3 Paul Oglesby; 4 JPL/NASA; 5 Paul
Oglesby; 6 (T) ©John Sanford/Photo Researchers, Inc.; 6 (B) ©Andy Crawford/DK Images; 8 Digital Vision; 9 NASA;
10 Getty Images; 11 (C)©Royal Observatory Edinburgh/SPL/Photo Researchers, Inc., (T)NASA, (B)©A Morton/Photo
Researchers, Inc.
ISBN: 0-328-23533-4
Copyright © Pearson Education, Inc All Rights Reserved Printed in the United States of America
This publication is protected by Copyright, and permission should be obtained from the publisher prior to any
prohibited reproduction, storage in a retrieval system, or transmission in any form by any means, electronic,
mechanical, photocopying, recording, or likewise For information regarding permission(s), write to
Permissions Department, Scott Foresman, 1900 East Lake Avenue, Glenview, Illinois 60025.
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by Peggy Bresnick Kendler
Objects
Trang 3What moves
around the Sun?
The Sun
The Sun is a star A star is a huge ball of hot,
glowing gases The Sun is 100 times as wide as
Earth Its surface temperature is about 5,500°C Its
center is much hotter!
The Sun is the star closest to Earth It appears
larger and brighter than any other star Other stars
look smaller because they are so far away
The Sun is closer to Earth
than any other star.
3
How Objects in the Solar System Move
Our home is planet Earth A planet is a large
body of matter that travels around a star, such as
the Sun Many planets have moons Our solar
system is made up of the Sun, the planets and
their moons, and other objects orbiting the Sun
The path an object takes as it moves around
the Sun is its orbit The Sun’s gravity has a strong
pull It keeps each planet in its orbit
Earth is part of the solar system
It orbits the Sun with the other planets.
Earth
Mars
Trang 4Planets of the Solar System
Mercury, Venus, Earth, and Mars are the four
planets nearest the Sun They orbit the Sun quickly
Jupiter, Saturn, Uranus, and Neptune are the
planets farthest from the Sun They orbit the Sun
slowly Asteroids of all sizes orbit the Sun between
planets An asteroid is a large piece of rock
Pluto, A Dwarf Planet
Pluto is very small, smaller than Earth’s moon
In 2006, scientists decided to call Pluto a “dwarf
planet.” Dwarf planets are small, round objects
that orbit the Sun
NASA’s Hubble Space Telescope was used
to take this picture of Pluto and its moon, Charon.
Pluto
Charon
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5
The Path of the Moon
Our Moon orbits Earth At the same time, Earth orbits the Sun The Moon turns on its axis as it orbits Every 27 days the Moon completes a turn It completes an orbit of Earth in about the same time
We always see the same side of the Moon This is because the Moon turns so slowly on its axis
Our Moon is the closest object to Earth Other than the Sun it is the brightest object in the sky
The Moon does not make light Its light comes from sunlight refl ecting off its surface
The Moon completes its orbit
in a little less than a month.
Trang 5How do we observe
objects in space?
Telescopes and the Night Sky
To see the Moon more clearly, look through a
telescope A telescope is a tool for making distant
objects appear nearer and larger Some telescopes
use curved mirrors The mirrors collect light The
light travels to a lens Telescopes that use these
mirrors help make objects appear bright in the
night sky
A telescope makes the Moon look larger It can help you see the Moon’s features.
7
Binoculars are two telescopes joined together
as a unit They are less powerful than telescopes
Binoculars and telescopes work best on clear nights, far from city lights
Before you look at the night sky, study charts of the stars and planets Next, observe the sky with your eyes Then try binoculars or a telescope
Planets look like stars They shine by light refl ected from the Sun Planets move across the sky’s star patterns
Binoculars are like telescopes But they are not as powerful.
Trang 6Viewing Distant Planets
Binoculars and telescopes can help you study
the solar system’s planets Use binoculars to see
Mars’s red surface Use a telescope to see the band
of clouds above Jupiter’s surface Jupiter’s Giant
Red Spot can also be spotted with a telescope It is a
storm three times the size of Earth!
This picture shows Mars’s
red soil The white dot at
the top is a polar ice cap.
9
Some planets are very far away from Earth They are too far away for people to see them clearly These planets are Uranus and Neptune The United States has sent space probes to study these planets
Neptune has a light blue color It is surrounded by rings.
Have you ever heard of the Giant Red Spot? It is a huge storm on Jupiter’s surface
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Trang 7Viewing Stars and Galaxies
On a clear night, you can see many stars With
a telescope, you can see even more stars Stars look
different from one another Some look brighter
than others Some look larger than others And
some appear to have a different color than others
A star might really be a galaxy A galaxy is a group
of stars, dust, and gas that are arranged together
Stars can have different
colors and sizes
11
Different Kinds of Stars
The Sun is our brightest star because it is closest
to Earth Does this mean that bright stars are closer to Earth than ones that are less bright? This
is not always so Stars differ in size Stars differ in the amount of light they make Many small stars make more light than big stars Stars that appear less bright may be closer to Earth than stars that appear bright
The Milky Way Galaxy
The Magellanic Cloud galaxies
A spiral galaxy
Trang 8asteroid a large piece of rock that orbits
the Sun
binoculars two telescopes joined together as
a unit
orbit the path an object takes as it
moves around the Sun
planet a large body of matter that
revolves around a star such as the Sun
solar system a system made up of the Sun, the
planets and their moons, and other objects that orbit the Sun
star a huge ball of hot, glowing gases
telescope a tool for making distant objects
appear nearer and larger
1 How does a telescope work?
2 What is a dwarf planet?
3 What two things does the Moon complete about once
every 27 days?
best way to see planets in the night sky Include a topic sentence and simple supporting facts and details.
discover any more planets in our solar system, and give
a reason for your answer
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