关于spacetravel的英语作文或资料

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问题描述:

拜托！spacetravel的英语作文或资料

解析:

Spacetravelbetsonadream.Todesignandbuildaspacecraftforspacetravel,youneedtobeabletofigureouthowbigtomakeit,howheavyitcanbe,howfastitwillhavetogo,howmuchfuelitneedsandsoforth.Forthat,youneedatheoryofhowobjectsmoveinspaceandhowtomakethecalculations.Overaperiodofnearlythreecenturies(from1600to1900),threebrilliantmen-JohannesKepler,IsaacNewtonandKonstantinTsiolkovsky,whosaidtheEarthisthecradleofmankind-onecannotremaininthecradleforever,workedoutalmostallthetheoriesofspaceflight.

By1951spacetravelplanshadbeemoregrandiose.FamedrocketscientistWernhervonBraunpredictedthatasuccessfulMarsmissioncouldbeacplishedwithasfewas46rocketsinaroundtripthatwouldtakethreeyears.InalaterinterviewwithTIME,vonBraunaffirmed,Manbelongswhereverhewantstogo-andhe'lldoplentywellwhenhegetsthere.

Thespaceagebeganin1957whentheSovietUnionlaunchedSputnik1,theworld'sfirstman-madesatellite.Alsoin1957,Sputnik2waslaunchedcarryingLaika,adogthatwasthefirstanimaltoorbittheEarth.In1961,YuriGagarinbecamethefirstpersontopilotaspacecraft.In1963,theUnitedStatesandtheSovietUnionstartedaracetoseewhocouldputamanontheMoonfirst.InMarchof1965,AlexeiLeonovoftheSovietUnionlefthisspacecrafttobeethefirstpersontowalkinspace.OnJuly20,1969,theUnitedStateswonwhenNeilArmstrongandBuzzAldrinlandedontheMoon'ssurface.TheosuperpowershavealsoputspacestationsintoorbitaroundtheEarth.Thesespacestructuresserveasbothahomeandalaboratoryforspacetravelers.TheUnitedStatescreatedandlaunchedthefirstreusablemannedspacecraft,theSpaceShuttle,in1981.