1、DestinationDestinationSaturnSaturnby Karen Alexanderby Karen AlexanderExpository TextPAIREDREADWhy the Stars TwinkleProgram:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28CV_CR14_LR_G3_U3W3L28_E_119278.indd 2CV_CR14_LR_G3_U3W3L28_E_119278.indd 213/02/12 11:40 AM13/02/12 11:40 AMSTRATEGIE
2、S&SKILLSAPhotography Credit:Cover NASA/JPL/Space Science Institute.*The total word count is based on words in the running text and headings only.Numerals and words in captions,labels,diagrams,charts,and sidebars are not included.ComprehensionStrategy:SummarizeSkill:Main Idea and Key DetailsVocabular
3、y StrategySuffixesELL Vocabularyrotates,spaceVocabularyamount,astronomy,globe,solar system,support,surface,temperature,warmth Content StandardsScienceEarth and Space ScienceWord Count:895*Program:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28Copyright The McGraw-Hill Companies,Inc.All r
4、ights reserved.No part of this publication may be reproduced or distributed in any form or by any means,or stored in a database or retrieval system,without the prior written consent of The McGraw-Hill Companies,Inc.,including,but not limited to,network storage or transmission,or broadcast for distan
5、ce learning.Send all inquiries to:McGraw-Hill EducationTwo Penn PlazaNew York,New York 10121ISBN:978-0-02-119278-6MHID:0-02-119278-2Printed in the United States.1 2 3 4 5 6 7 8 9 DOC 15 14 13 12 11 10IFCIBC_CR14_LR_G3_U3W3L28_E_119278.indd 2IFCIBC_CR14_LR_G3_U3W3L28_E_119278.indd 213/02/12 11:41 AM1
6、3/02/12 11:41 AMPAIREDREADChapter 1Exploring Saturn .2Chapter 2Mission to Saturn .8Chapter 3Storm on Saturn .13Respond to Reading.15Why the Stars Twinkle .16Glossary/Index.19Focus on Science.20by Karen Alexanderby Karen AlexanderDestination SaturnEssential QuestionWhat do we know about Earth and its
7、 neighbors in space?Program:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28001_009_CR14_LR_G3_U3W3L28_E_119278.indd 1001_009_CR14_LR_G3_U3W3L28_E_119278.indd 113/02/12 11:44 AM13/02/12 11:44 AMChapter 1Exploring SaturnPeople have been studying astronomy for thousands of years.Astronomy i
8、s the study of stars and planets.People discovered the planet Saturn before telescopes were invented.Now we can learn more about Saturn by using spacecraft.Saturn is the second biggest planet in the solar system.The Solar SystemMercuryVenusEarthMarsJupiterSaturnUranusNeptuneSun2Program:CR 14Componen
9、t:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28Stocktrek/Alamy001_009_CR14_LR_G3_U3W3L28_E_119278.indd 2001_009_CR14_LR_G3_U3W3L28_E_119278.indd 213/02/12 11:44 AM13/02/12 11:44 AMSaturn is not a globe.When people look at Saturn through a telescope,it looks like someone pushed the top and bottom toge
10、ther.This is because Saturn rotates very fast.Saturn is mostly gas.Saturn cannot support human life.Saturn is many times bigger than Earth.SaturnEarthGas PlanetSaturn is a gas planet.Jupiter,Uranus,and Neptune are gas planets,too.Gas planets are bigger than the planets that are made of metal and roc
11、k.Those are called terrestrial planets.Earth is a terrestrial planet.3Program:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28(tl)NASA/JPL/Space Science Institute,(tr)NOAA/NASA GOES Project 001_009_CR14_LR_G3_U3W3L28_E_119278.indd 3001_009_CR14_LR_G3_U3W3L28_E_119278.indd 313/02/12 11:44
12、AM13/02/12 11:44 AMThe Rings of SaturnAll the gas planets have rings,but Saturn has the biggest rings.The rings are made of pieces of ice,rock,and dust.These vary in size.Some pieces are the size of a grain of sand.Some pieces are the size of a mountain.Scientists think Saturns rings may have been f
13、ormed from moons or other space objects.The past tense of verbs ending in-y is usually formed by dropping the-y and adding-ied.Can you find an example of a verb that forms its past tense in that way on this page?LanguageDetectiveSaturns ringsProgram:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning Medi
14、aLevel:284NASA/JPL/Space Science Institute001_009_CR14_LR_G3_U3W3L28_E_119278.indd 4001_009_CR14_LR_G3_U3W3L28_E_119278.indd 413/02/12 11:44 AM13/02/12 11:44 AM Scientists have discovered eight groups of rings.There are many rings within each group.There are spaces between the rings.Discovering the
15、RingsGalileo was an Italian astronomer.He was the first person to see Saturns rings through a telescope.Galileo could not see the rings clearly.He drew the rings as if they were handles.In 1659,a Dutch astronomer named Huygens figured out that the shape around Saturn was a ring.In 1675,another astro
16、nomer,Cassini,realized that Saturn had more than one ring.GalileoIn Other Words realized.En espaol,figured out quiere decir descubri.5Program:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28Library of Congress Prints and Photographs Division LC-USZ62-7923001_009_CR14_LR_G3_U3W3L28_E_11927
17、8.indd 5001_009_CR14_LR_G3_U3W3L28_E_119278.indd 513/02/12 11:44 AM13/02/12 11:44 AMMany MoonsSaturn has many moons.Fifty-three of the moons have names.Titan was the first moon discovered.Titan is also the biggest moon.In fact,Titan is bigger than the planet Mercury.The moons are different.Some moon
18、s are icy,some moons are huge,and some moons are tiny.Some moons even have their own rings.The moon Phoebe travels around Saturn in the opposite direction from the way Saturn travels.SaturnPhoebeProgram:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:286NASA/JPL-Caltech001_009_CR14_LR_G3_U3
19、W3L28_E_119278.indd 6001_009_CR14_LR_G3_U3W3L28_E_119278.indd 613/02/12 11:44 AM13/02/12 11:44 AMSome of Saturns moons orbit inside the rings.Two of the moons share the same orbit.These moons orbit within 30 miles of each other.The moon on the outside catches up with the moon on the inside every fou
20、r years.They change places.Did You Know?Did You Know?Some of Saturns moons are white.Astronomers believe these moons are made of ice.Dione is one of Saturns icy moons.Some of Saturns rings can be seen behind Dione.DioneSTOP AND CHECKWhat have you learned about Saturn s moons?7Program:CR 14Component:
21、LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28NASA/JPL/Space Science Institute001_009_CR14_LR_G3_U3W3L28_E_119278.indd 7001_009_CR14_LR_G3_U3W3L28_E_119278.indd 713/02/12 11:44 AM13/02/12 11:44 AMChapter 2 Mission to Saturn In 1997,scientists sent a spacecraft on a mission to study Saturn and its moon
22、s and rings.The Cassini-Huygens spacecraft took seven years to travel from Earth to Saturn.The spacecraft orbited Saturn,and sent information about Saturn back to Earth.The spacecraft separated into two spacecraft,called Huygens and Cassini.The Huygens spacecraft landed on Titan,and sent information
23、 about T itan back to Earth.Orbited is the past tense of orbit.Find another verb in the past tense form on this page.LanguageDetectivespacecraftSaturn8Program:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28NASA001_009_CR14_LR_G3_U3W3L28_E_119278.indd 8001_009_CR14_LR_G3_U3W3L28_E_119278.
24、indd 813/02/12 11:44 AM13/02/12 11:44 AMThe Long Way RoundSaturn is 800 million miles from Earth,but the Cassini-Huygens spacecraft traveled about two billion miles to get to Saturn.Why?A spacecraft cannot carry enough fuel for such a long journey,so gravity is helpful in space travel.The spacecraft
25、 built up speed as it flew past Earth,Venus,and Jupiter.This saved fuel.Then the spacecraft floated through space without using its engines.It used gravity.When the spacecraft got to Saturn,it used its engines to slow down.This is an artists idea of the spacecraft landing on Titan.Huygens s9Program:
26、CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28Craig Attebery/NASA001_009_CR14_LR_G3_U3W3L28_E_119278.indd 9001_009_CR14_LR_G3_U3W3L28_E_119278.indd 913/02/12 11:44 AM13/02/12 11:44 AMThe Cassini-Huygens spacecraft provided a huge amount of information about Titan.Astronomers think that
27、Titan is similar to Earth when Earth was young.Titan is the only moon in this solar system that has an atmosphere.Titans atmosphere is similar to Earths atmosphere.The landscape of Titan is similar to the landscape of Earth.Titan has valleys and mountains.Titan has huge sand dunes.Titan might also h
28、ave weather similar to the weather on Earth.Scientists believe there may be an ocean under the surface of Titan.This is an artists impression of Titan.10Program:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28 (t)CassiniImagingTeam NASA/JPL/SSI(b)StevenHobbs/NASA/JPLNASA/JPL010_015_CR14_L
29、R_G3_U3W3L28_E_119278.indd 10010_015_CR14_LR_G3_U3W3L28_E_119278.indd 1013/02/12 11:47 AM13/02/12 11:47 AMHyperion is another of Saturns moons.It looks like a pointy piece of rock.This is unusual.Most objects that rotate in space are round.Huygens was the first spacecraft to land in the outer solar
30、system.CassiniHuygensHyperionProgram:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28 11(t)Cassini Imaging Team,NASA/JPL/SSI,(b)Steven Hobbs/NASA/JPL010_015_CR14_LR_G3_U3W3L28_E_119278.indd 11010_015_CR14_LR_G3_U3W3L28_E_119278.indd 1113/02/12 11:47 AM13/02/12 11:47 AMThe moon Enceladus l
31、ooks bright because it is covered with ice.Icy water sprays from the moon Enceladus.The water is similar to Earths oceans.Scientists believe there may be salt water beneath the icy crust of the moon.The temperature on Enceladus is warmer than scientists expected on an icy moon.Scientists also believ
32、e there is warmth deep under the surface of Enceladus.Icy water rises from Enceladus.EnceladusSaturnSTOP AND CHECKWhat is unusual about Hyperion?icy wateratur12Program:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28 NASA/JPL010_015_CR14_LR_G3_U3W3L28_E_119278.indd 12010_015_CR14_LR_G3_U3
33、W3L28_E_119278.indd 1213/02/12 11:47 AM13/02/12 11:47 AMThe Cassini-Huygens space mission ends in September 2017.The spacecraft has kept track of a huge thunderstorm on Saturn.The storm stretches around the whole planet.The storm sends gas into Saturns atmosphere.The storm covers an area eight times
34、 bigger than the area of Earth.The storm is more powerful than any storm on Earth.Chapter 3 Storm on SaturnDid You Know?Did You Know?It is rare to have storms on Saturn.In Other Words stayed informed about or kept a record of.En espaol,kept track of quiere decir ha mantenido seguimiento de.13Program
35、:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28 NASA/JPL010_015_CR14_LR_G3_U3W3L28_E_119278.indd 13010_015_CR14_LR_G3_U3W3L28_E_119278.indd 1313/02/12 11:47 AM13/02/12 11:47 AMPeople explore space to discover more about the universe.Some want to know if there is life on other planets.Th
36、e Cassini-Huygens space mission has given scientists information about Saturn,its moons,and its rings.The information about Titan and Enceladus is very exciting.Titan may teach us about Earth long ago.Enceladus has warmth,water,and organic chemicals.These elements are necessary for life.Other amazin
37、g discoveries may be made in the future!STOP AND CHECKWhy do people explore space?Saturn14Program:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28 NASA/JPL/Space Science Institute 010_015_CR14_LR_G3_U3W3L28_E_119278.indd 14010_015_CR14_LR_G3_U3W3L28_E_119278.indd 1413/02/12 11:47 AM13/02/
38、12 11:47 AMSummarizeSummarize what you have learned about Saturn.Use the Main Idea and Details Chart to help you.Text Evidence 1.How do you know that Destination Saturn is an expository text?GENRE 2.Reread page 10.Why are scientists interested in Titan?MAIN IDEA AND KEY DETAILS 3.What does icy on pa
39、ge 12 mean?Rewrite the sentence using ice instead of icy.SUFFIXES 4.Write to describe reasons that scientists find Enceladus interesting?WRITE ABOUT READINGMain IdeaDetailDetailDetail15Program:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28 010_015_CR14_LR_G3_U3W3L28_E_119278.indd 15010_
40、015_CR14_LR_G3_U3W3L28_E_119278.indd 1513/02/12 11:47 AM13/02/12 11:47 AMLong,long ago,Earth and the sky were close together.People on Earth could touch the sky.One day,a woman went outside to grind rice for her family.The woman had lovely,silky hair.She brushed it often.The woman was very proud of
41、her jewelry and always wore it.It was a hot day.The woman did not want to work.She put a large amount of rice into a wooden bowl.She decide to grind all the rice at once.The woman started to grind the rice with a pestle.The work was difficult,so the woman got angry.Compare TextsYou have read about a
42、 space mission to Saturn.Now learn how people used to explain the universe.WHY THE STARS TWINKLE16Program:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28 Illustration:Pamela Becker016_020_CR14_LR_G3_U3W3L28_E_119278.indd 16016_020_CR14_LR_G3_U3W3L28_E_119278.indd 1613/02/12 11:48 AM13/02
43、/12 11:48 AMThe woman ground the rice harder.She lifted the pestle higher and higher.Her gold ring rubbed the skin on her finger,and she got a blister.She put her ring on the sky.The woman s silver comb fell out of her hair.She hung the comb on the sky.The woman s necklace got in her way,so she hung
44、 the necklace on the sky,too.The woman was so busy working,she didn t realize what she was doing.Each time she lifted the pestle,she pushed the sky farther away.pestle17Program:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28necklaceringcombrice016_020_CR14_LR_G3_U3W3L28_E_119278.indd 170
45、16_020_CR14_LR_G3_U3W3L28_E_119278.indd 1713/02/12 11:48 AM13/02/12 11:48 AMMake ConnectionsWhy do you think Why the Stars Twinkle was written?ESSENTIAL QUESTION How is the reason for the stars,moon,and sun in Why the Stars Twinkle different from the descriptions of space in Destination Saturn?TEXT
46、TO TEXTThe woman finished her work.The woman looked at the sky.The sky was now far above her.The woman could see her ring,comb,and necklace,but she could not reach them.We can still see the jewelry.The woman s silver comb is the moon,and her gold ring is the sun.The woman s sparkly necklace became t
47、he stars that twinkle across the surface of the sky.moonstars18Program:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28 Illustration:Pamela Becker016_020_CR14_LR_G3_U3W3L28_E_119278.indd 18016_020_CR14_LR_G3_U3W3L28_E_119278.indd 1813/02/12 11:48 AM13/02/12 11:48 AMGlossaryIndexEnceladus,
48、12,14Hyperion,11moons,4,68,1012,14rings,48,14telescopes,2,3,5,Titan,6,810,14astronomer a person who studies the stars and planets(page 5)atmosphere the gases that surround a planet(page 10)gravity the natural force that pulls objects toward one another(page 9)orbit to follow a path,usually circular,
49、around a planet,moon,or other space body(page 7)organic chemicals elements that are the basis of life(page 14)terrestrial planets planets made of rock and metal (page 3)19Program:CR 14Component:LRG3 U3 W3 EPDFVendor:Learning MediaLevel:28016_020_CR14_LR_G3_U3W3L28_E_119278.indd 19016_020_CR14_LR_G3_
50、U3W3L28_E_119278.indd 1913/02/12 11:48 AM13/02/12 11:48 AMAlikeDifferentStep 3Step 2Step 1Purpose To compare two planets.What to DoWith a partner,choose a planet that you are interested in,other than Saturn.Research the planet.Find out where your planet is,how big it is,and if it has a moon or rings
