byBeauWrightË|xHSKBPDy501197zv*:+:!:+:!>ISBN-13:978-0-15-350119-7ISBN-10:0-15-350119-7GRADE3Lesson29WORDCOUNT487GENREExpositoryNonfictionLEVELELLHarcourtLeveledReadersOnlineDatabaseCover,p.3,©NASA/Corbis;p.8,©KazuyoshiNomachi/Corbis;p.9,©PaulA.Souders/CORBIS;p.10–11,©DannyLehman/Corbis;p.12,©FransLemmens/zefa/Corbis;p.13,p.14,©PhotoDisc.Diagramsp.4,p.5,p.6–7,JoeLeMonnierCopyright©byHarcourt,Inc.Allrightsreserved.Nopartofthispublicationmaybereproducedortransmittedinanyformorbyanymeans,electronicormechanical,includingphotocopy,recording,oranyinformationstorageandretrievalsystem,withoutpermissioninwritingfromthepublisher.RequestsforpermissiontomakecopiesofanypartoftheworkshouldbeaddressedtoSchoolPermissionsandCopyrights,Harcourt,Inc.,6277SeaHarborDrive,Orlando,Florida32887-6777.Fax:407-345-2418.HARCOURTandtheHarcourtLogoaretrademarksofHarcourt,Inc.,registeredintheUnitedStatesofAmericaand/orotherjurisdictions.PrintedinChinaISBN10:0-15-350119-7ISBN13:978-0-15-350119-7OrderingOptionsISBN10:0-15-349938-9(Grade3ELLCollection)ISBN13:978-0-15-349938-8(Grade3ELLCollection)ISBN10:0-15-357269-8(packageof5)ISBN13:978-0-15-357269-2(packageof5)Ifyouhavereceivedthesematerialsasexaminationcopiesfreeofcharge,HarcourtSchoolPublishersretainstitletothematerialsandtheymaynotberesold.Resaleofexaminationcopiesisstrictlyprohibitedandisillegal.Possessionofthispublicationinprintformatdoesnotentitleuserstoconvertthispublication,oranyportionofit,intoelectronicformat.1234567891098512111009080706byBeauWrightEarthlookslikeablueplanetfromspace.Theearthlooksbluebecausewatercoversaboutthree-quartersoftheearth.NootherplanetislikeEarth.Let’stakealookatwhatmakesourplanetspecial.3sunEarthEarthEarthmovesthroughspaceintwowaysatthesametime.First,theearthmovesaroundthesuninapathcalledanorbit.Earthalsospinsaroundonitsaxislikeatoytop.Anaxisisanimaginarystickthatrunsthroughthecenteroftheearth.4ThespinningofEarthcausesdaytimeandnighttime.WhenonesideofEarthfacesthesun,itisdaytimethere.Itisnighttimeon...
