byScarlettJonesillustratedbyGeoffreyMcCormackbyScarlettJonesillustratedbyGeoffreyMcCormackCopyright©byHarcourt,Inc.Allrightsreserved.Nopartofthispublicationmaybereproducedortransmittedinanyformorbyanymeans,electronicormechanical,includingphotocopy,recording,oranyinformationstorageandretrievalsystem,withoutpermissioninwritingfromthepublisher.RequestsforpermissiontomakecopiesofanypartoftheworkshouldbeaddressedtoSchoolPermissionsandCopyrights,Harcourt,Inc.,6277SeaHarborDrive,Orlando,Florida32887-6777.Fax:407-345-2418.HARCOURTandtheHarcourtLogoaretrademarksofHarcourt,Inc.,registeredintheUnitedStatesofAmericaand/orotherjurisdictions.PrintedinChinaISBN10:0-15-351514-7ISBN13:978-0-15-351514-9OrderingOptionsISBN10:0-15-351213-X(Grade3AdvancedCollection)ISBN13:978-0-15-351213-1(Grade3AdvancedCollection)ISBN10:0-15-358104-2(packageof5)ISBN13:978-0-15-358104-5(packageof5)Ifyouhavereceivedthesematerialsasexaminationcopiesfreeofcharge,HarcourtSchoolPublishersretainstitletothematerialsandtheymaynotberesold.Resaleofexaminationcopiesisstrictlyprohibitedandisillegal.Possessionofthispublicationinprintformatdoesnotentitleuserstoconvertthispublication,oranyportionofit,intoelectronicformat.1234567891098512111009080706Highoverhead,thesunshinesdown.Youcanfeelitwarmyourface.Eachday,heatandlightfromthesuntravelmillionsofmilestoreachthesurfaceoftheearth.Plantsusetheenergyofthesuninordertogrow.Animalsrelyonplantsforfood.Withoutthesun,lifewouldnotexisthereonEarth.Thesunresemblesalarge,yellowballoffirethatstayssteadyinthesky.ItisthecloseststartoEarth.Thatiswhyitlooksbiggerandbrighterthanotherstars.3Thesunisthestaratthecenterofoursolarsystem.Earthandtheotherplanetsrevolvearoundthesun.Thesunandthestarsyouseeatnightaresimilarinmanyways.Allstarsconsistofgases.Onegasiscalledhydrogen.Hydrogenisusedtomakelightandheatenergy.Itislightenergythatweseecomingfromthestarsatnight.TheheatenergyfromthesunwarmsEarth.4TheraysofheathitEarth,andEarthreflectssomeoftheraysbackintospace.Theseraysheatuptheairaround...
