2023年雅思剑桥9听力和阅读文本_第1页
2023年雅思剑桥9听力和阅读文本_第2页
2023年雅思剑桥9听力和阅读文本_第3页
2023年雅思剑桥9听力和阅读文本_第4页
2023年雅思剑桥9听力和阅读文本_第5页
已阅读5页,还剩119页未读 继续免费阅读

下载本文档

版权说明:本文档由用户提供并上传,收益归属内容提供方,若内容存在侵权,请进行举报或认领

文档简介

雅思听力阅读文本IELTS剑9(TEST1)听力Section1W:Goodevening.King'srestaurant.M:Goodevening.I'mringingaboutthejobIunderstandyouhavevacant?W:Oh,yes.M:I'dliketofindoutafewmoredetailsifImay.W:Yes,ofcourse.CanItakeyourname?M:It'sPeterChin.W:Ok,Peter.Well,ifyouwanttoaskaboutthejobandthenifwe'rebothstillinterested,wecouldarrangeyoutocomeforaninterview.M:Great,thanks.I'mafraidImissedtheadvertforthejobbutIheardaboutitfromafriend.W:That'snoproblematall.Whatwouldyouliketoknow?M:Well,um,whatsortofworkisit-washingup?W:It'sansweringthephone.M:Oh,right,fine.W:Andnotwaitingattable.M:That'llbegood.Andhowmanynightsaweekwoulditbe?W:Well,we'rereallyonlybusyattheweekend.M:Sotwonights?W:Threeactually,soitwouldworkout12hoursaweek.M:That'dbefine.Itwouldn'tinterferewithmystudies.W:Areyouintheuniversity?M:Yes,firstyearPhysicsstudent.W:Oh,rightM:BecauseI'mnotanEUnational,wouldIneedaworkpermit?W:Yes,youwould.Justgetyoututortosignit.M:Thatwouldn'tbeaproblemifIweretogetthejob.Um,whereexactlyistherestaurant?W:Well,wehavetwobranches-theonewe'rerecruitingforisinHillsdunneroad.M:Em,Idon'tknowthat.Howdoyouspellit,please?W:It'sH-I-doubleL-S-D-U-doubleN-ERoad.M:Gotthat,thanks.Isitnearabusstop?W:Yes,thenearestonewouldprobablybejustbesidethelibrary.M:Oh,yes,Iknowit.That'llbefineforme.AndcouldIaskaboutthepay?W:We'reoffering4.45poundsanhour.M:That'sverygood.Mylastjobwas3.95anhour.W:Wefeelit'sprettygoodandwealsooffersomegoodfringebenefits(附加福利).M:Really?W:Well,wegiveyouafreedinner,soyoueatwell.M:Right.Betterthanhostelfood.W:Wecertainlyhopeso.Andwealsoofferextrapayforworkingonnationalholidays.M:Oh,that'sareallygoodperk(额外收入),isn'tit?W:Yes,wethinkso.Andthenbecauseofthedifficultiesofgettingpublictransport,ifyou'reworkingafter11o'clock,wedriveyouhome.M:Oh,that'sgoodtoknow.W:We'dcertainlybeinterestedininvitingyouforaninterview,ifyou'restillinterested?M:Oh,yes,certainly.CouldIjustalsoaskwhatqualitiesyou'relooingfor?W:Well,forthisparticularjob,wewantaclearvoice,whichyouobviouslydohaveM:Thanks.W:Andyoumustbeabletothinkquickly,youknow.M:Well,IhopeI'd...W:So,whencouldyoucomeinforaninterview?We'reactuallyquitequiettonight?M:Sorry,Icouldn'tcometonightortomorrow,I'mafraid.Thursdayisok,that'dbe22ndofOctober.W:Fine,after5pm?M:Yes,fine.Would6o'clockbeok?W:Perfect.Andcouldyoubringalongthenamesoftworeferees?M:Yes,that'sfine.Noproblem.W:Good,Ilookforwardtoseeingyou.M:Oh,bytheway,whoshouldIaskfor?W:Oh,yes,ofcourse,sorry.MynameisSamiraManuja.M:Canyouspellthatplease?W:M-a-n-u-j-aM:Ok,I'vegotthat.Thankyouverymuch.W:Lookforwardtoseeinglater...听力Section2M:NowwegotoJanewhoisgoingtotellusaboutwhat'shappeningintownthisweekend.W:Right,thanks,Andrew,andnowontowhat'snew,anddowereallyneedyetanothersportsshoppingBradcaster?Well,mostofyouprobablyknowSportsWorld-thebranchofaDanishsportsgoodscompanythatopenedafewyearsago-it'sattractedalotofcustom,andsothecompanyhasnowdecidedtoopenanotherbranchinthearea.It'sgoingtobeintheshoppingcentertothewestofBradcaster,sothatwillbegoodnewsforallofyouwhofoundtheoriginalshopintheNorthofthetownhardtogetto.IwasinvitedtoaspecialpreviewandIcanpromiseyou,thisistheultimateinsportsretailing.Thewholeplacehasbeengivenanewminimalist(极简主义者)lookwiththecompany'ssignaturecolorsofblackandred.Thefirstthreefloorshaveahugerangeofsportsclothingaswellastheequipment.Andonthetopfloor,thereisacafeandabook&DVDsection.You'llfindallthewell-knownnamesaswellassomelesswell-knownones.Iftheyhaven'tgotexactlywhatyouwantinthestock,theypromisedtogetitforyouin10days,unliketheotherstore,whereitcantakeupto14days.Theycoverallthemajorsports,includingfootball,tennis,andswimming,buttheyparticularlyfocusonrunningandtheyclaimtohavethewidestrangeofequipmentinthecountry.Aswellasthat,awholesectionofthethirdfloorisdevotedtosportsbags,includingthelatestdesignfromtheStates-Ifyoucan'tfindwhatyouwanthere,itdoesn'texist.Theshopwouldbeopenfrom9amthisSaturday,andifyougoalongtotheopeningthenyou'llhavethechancetomeetthenational400metersrunningchampionPaulKing,who'scomingalongtoopentheshop,andhewillbestayarounduntilaboutthemiddaytochattoanyfanswhowanttomeethimandsignautographs.Thentherewillbeawholerangeofspecialattractionsallweekend.Therewillbefreeticketsforlocalsportingeventsforthefirst50customers,andalsoaspecialcompetitionopentoall,justanswer15outof20sportsquestionscorrectlytowinasignedcopyofPaulKing'sDVD'SpringTips',whilethefirstpersontogetallthequestionscorrectgetsayear'sfreemembershipoftheBradcasterGym.AllentrancewillreceiveaspecialSportscalendarwithdetailsofallBradcasterfixturesinthecomingyear.Oneofthespecialopeningoffersisafitnesstest-acompletereviewofyourcardiacfitnessandmuscletone,actuallydoneintheshopbyqualifiedstaff.Thiswouldnormallycost30poundsbutisavailableathalfpriceforthismonthonly.Thereareonlyalimitednumberofplacesavailableforthis,sotomakeabookingphone560341.Inaddition,ifyouopenanaccountyougetlotsmorespecialoffersincludingthechancetotryouttheequipmentatthespecialopeningevenings...听力Section3Pro:Beforewestart,SpirosandHiroko,thanksforcomingintodaytotalkaboutyourrecentstudyexperiencesandcongratulationstoyoubothindoingsowellinthefirstsemesterexams.I'dliketodiscusswithyouthevalueoftheEnglishforAcademicPurposescourseyoudidherelastyearbeforestartingyouruniversitycourse.Spiros,ifIcouldstartwithyou,whatpartsoftheprogrammehavenowprovedtobeparticularlyvaluabletoyou?S:Ithinkthathavingtodoaseminarpresentationreallyhelpedme.Forexample,acoupleofweeksagoinourmarketingsubject,whenitwasmyturntogivepresentation,Ifeltquiteconfident.Ofcourse,IwasstillnervousbutbecauseIhaddoneonebefore,Iknewwhattoexpect.Also,IknowIwaswellpreparedandIhadpractisedmytiming.Infact,Ithinkthatinrelationtosomeoftheotherpeopleinmygroup,Ididquiteagoodjobbecausemyoverallstylewasquiteprofessional.Pro:WhataboutyouHiroko?H:Mmm,that'sinteresting.Inmygroup,Iwasreallysurprisedbythewaystudentsdidtheirpresentations-theyjustreadthenotesaloud.Canyoubelievethat?Theydidn'tworryabouttheirpresentationstyleorkeepingeyecontactwiththeiraudience-andIrememberthatthesethingswerereallystressedtousinthecoursehere.Pro:So,howdidyouapproachyourpresentationHiroko?H:Well,tospeakfrankly,Ireadmynotestoo.Atthetime,itwasarelieftodoitthisway,butactuallywhenIhadfinishedIdidn'tfellanyrealsenseofsatisfaction.Ididn'tfeelpositiveabouttheexperienceatall.S:That'sapity.YouknowalthoughIwaspleasedwithmypresentation,I'mnotsopleasedwithmyactualperformancerightnowinthetutorials-duringthewholesemesterI'venotsaidanythinginourtutorialdiscussions.Notaword.H:Really,Spiros,whyisthat?Dotheotherstudentstalktoomuch?S:It'spartlythat,butit'smostlybecauseIhavehadnoconfidencetospeakout.Theirstyleofspeakingissodifferen-it'snotthestylewewereusedtoduringthecourse.Therearesomanycolloquialism(白话,口语,俗话,方言),theynotverypoliteandsometimestheyseemstobenoorderintheirdiscussion.Alsotheyareveryfamiliarwitheachother,sobecausetheyknoweachother'shabits,theycanleteachotherintothediscussion.H:You'reright,Spiros.I'veexperiencedthattoo.H:Formostofthissemester,I'vesaidabsolutelynothingintwotutorials.ButrecentlyI'vebeentryingtospeakupmoreandIjustjumpin.AndI'venoticedaninterestingthing.I'venoticedthatiftheythoughtmypointwasinterestingandnew,thenthenexttimetheyactuallyaskedformyopinion,andthenitwasmucheasierformetobepartofthediscussion.S:That'sgreat,Hiroko.Ihopethathappensformenextsemester-I'llhavetoworkhardtofindsomeinterestingpoints.Whathelpyoutofindtheseideas?H:Ithinkthatonethingthathelpedmewiththiswasthereading.I'vehadtodosomuchreadingthissemesterjusttohelpmetomakesenseofthelectures.AtfirstIcouldn’tunderstandwhatthelecturersweretalkingabout,soIhadtoturntothebooksandjournals.EverynightIreadforhours,usingthelistsofreferencesthatweregiven,andImadepagesofnotes.Atbreakfast,Ireadandreadmynotesagain.Thishabithashelpedmetofollowtheideasinthelectures,andit'salsogivenmesomeideastouseinthetutorials.S:ButIdidsomuchreadingsanyway-Idon'tthinkthere'sanytimeleftoverforanythingextra.Myreadingspeedisstillquiteslow,thoughI'mmuchbetteratdealingwithvocabularythanIusedtobe.Pro:Whatelsedoyouthinkwecouldaddtothecourseprogramtohelpwiththisreadingproblem?S:Er,there'snotreallyanythingbecauseit'smyproblem.Irememberweweregivenlongarticlestoread.Wedidn'tlikethatbutnowIrealisethatreadingthoselongarticleswasgoodpreparationforthethingsIneedtoreadnow.Also,inclassweregularlyhadspeed-readingtaskstodo,andwekeptarecordofourreadingspeed,sotheteacherswereencouragingustoworkonthat.H:That'strue,Spiros,butwhatwereadcouldhavebeendifferent.SometimeintheEnglishclassIfeltfrustratedwhenIhadtoreadarticlesabouttheenvironmentorhealthoreducation,becauseIwantedtoconcentrateonmyownfield,butwedidn'treadanythingaboutengineering.So,IthinkIwastedsometimelearningvocabularyIdidn'tneed.Pro:Butsurelythisstrategiesyouweretaughtfordealingwiththatvocabularywerehelpful?H:Yes,butpsychologicallyspeaking,Iwouldhavefeltmuchbetterworkingonreadingfrommyownfield.WhatdoyouthinkSpiros?S:Well,Iagree.Thatwouldhavehelpedmyconfidencetoo,andIwouldhavebeenmoremotivated.Anditwasgoodthoughthatwecouldworkonourowntopicswhenwewrotetheresearchassignments.Pro:Ok,that'smoveontowritingnow...听力Section4Goodafternooneveryone.Well,withsomeofyouwillgooutonfieldworkit'stimelythatinthisafternoon'ssessionI'llbesharingsomeideasaboutthereasonswhygroupsofwhalesanddolphinssometimesswimashorefromthesearightontothebeachand,mostoften,dieinwhatwereknownas"massstranding".Unfortunately,thistypeofeventisafrequentoccurrenceinsomeofthelocationsthatyou'llbetravellingto,wheresometimesthetidegoesoutsuddenly,confusingtheanimals.However,therearemanyothertheoriesaboutthecausesofmassstrandings.Thefirstisthatthebehaviorislinkedtoparasites.It'softenfoundthatstrandedanimalswereinfestedwithlargenumbersofparasites.Forinstance,atypeofwormiscommonlyfoundintheearsofdeadwhales.Sincemarineanimalsrelyheavilyontheirhearingtonavigate,thistypeofinfestationhasthepotentialtobeveryharmful.Anothertheoryisrelatedtotoxins,orpoisons.Thesehavealsobeenfoundtocontributetothedeathofmanymarineanimals.Manytoxins,asI'msureyou'reaware,originatefromplants,oranimals.Thewhaleingeststhesetoxinsinitsnormalfeedingbehaviorbutwhetherthesepoisonsdirectlyorindirectlyleadtostrandinganddeath,seemstodependuponthetoxininvolved.In1988,forexample,fourteenhumpbackwhalesexclaimedafterstrandingalongthebeachesofCapeCodewerefoundtohavebeenpoisonedaftereatingtunathatcontainedsaxitoxin,thesametoxinthatcanbefataltohumans.Alternatively,ithasalsobeensuggestedthatsomeanimalsstrandedaccidentallybyfollowingtheirpreyashoreintheconfusionofthechase.In1995DavidThurstonmonitoredpilotwhalesthatbeachedafterfollowingthesquidashore.However,thisideadoesnotseemtoholdtrueforthemajorityofmassstrandingsbecauseexaminationoftheanimals'stomachcontentsrevealthatmosthadnotbeenfeedingastheystranded.Therewerealsosomenewtheories,whichlinkstrandingstohunmans.Agrowingconcernisthatloudnoisesintheoceancausestranings.Noisessuchasthesecausedbymilitaryexercisesareofparticularconcernandhavebeenpinpointedasthecauseofsomestrandingsoflate.Oneofthese,amassstrandingofwhalesinintheBahamasconincidedcloselywithexperimentsusinganewsubmarinedetectionsystem.Thereareseveralfactorsthatmadethisstrandingstandoutasdifferentfrompreviousstrandings.Thisledresearcherstolookforanewcause.Forone,allthestrandedanimalswerehealthy.Inaddition,theanimalswerespreadoutalong38kilometersofcoast,whereasit'smorefortheanimalstobefoundinagroupwhenmassstrandingsoccur.Afinaltheoryisrelatedtogroupbehaviour,andsugeststhatseamammalscannotdistinguishbetweensickandhealthyleadersandwillfollowsickleaders,eventoaninevitabledeath.Thisisaparticularlyinterestingtheorysincethewhalesthatarethoughttobemostsocial-thetoothedwhaled-arethegroupthatstrandthemostfrequently.Thetheoryisalsosupportedbyevidencefromadolphinstrandingin1994.Examinationofthedeadanimalsrevealedthatapartfromtheleader,alltheothershadbeenhealthyatthetimeoftheirdeath.Withoutoneconsistenttheoryhoweveritisveryhardforustodoanythingaboutthisphenomenonexcepttoassistanimalwhereandwhenwecan.Strandingnetworkshavebeenestablishedaroundtheworldtoaidinrescuinganimalsandcollectingsamplesformthosethatcouldnotbehelped.IrecommendedJohnConnor'sMarineMammalsashoreasanexcellentstartingpointifyou'reinterestedinfindingoutmoreabouttherenetworks,orestablishingoneyourself.ReadingPassage1WilliamHenryPerkinThemanwhoinventedsyntheticdyesWilliamHenryPerkinwasbornonMarch12,1838,inLondon,England.Asaboy,Perkin’scuriositypromptedearlyinterestsinthearts,sciences,photography,andengineering.Butitwasachancestumblinguponarun-down,yetfunctional,laboratoryinhislategrandfather’shomethatsolidifiedtheyoungman’senthusiasmforchemistry.AsastudentattheCityofLondonSchool,Perkinbecameimmersedinthestudyofchemistry.Histalentanddevotiontothesubjectwereperceivedbyhisteacher,ThomasHall,whoencouragedhimtoattendaseriesoflecturesgivenbytheeminentscientistMichaelFaradayattheRoyalInstitution.Thosespeechesfiredtheyoungchemist’senthusiasmfurther,andhelaterwentontoattendtheRoyalCollegeofChemistry,whichhesucceededinenteringin1853,attheageof15.AtthetimeofPerkin’senrolment,theRoyalCollegeofChemistrywasheadedbythenotedGermanchemistAugustWilhelmHofmann.Perkin’sscientificgiftssooncaughtHofmann’sattentionand,withintwoyears,hebecameHofmann’syoungestassistant.Notlongafterthat,Perkinmadethescientificbreakthroughthatwouldbringhimbothfameandfortune.Atthetime,quininewastheonlyviablemedicaltreatmentformalaria.Thedrugisderivedfromthebarkofthecinchonatree,nativetoSouthAmerica,andby1856demandforthedrugwassurpassingtheavailablesupply.Thus,whenHofmannmadesomepassingcommentsaboutthedesirabilityofasyntheticsubstituteforquinine,itwasunsurprisingthathisstarpupilwasmovedtotakeupthechallenge.Duringhisvacationin1856,Perkinspenthistimeinthelaboratoryonthetopfloorofhisfamily’shouse.Hewasattemptingtomanufacturequininefromaniline,aninexpensiveandreadilyavailablecoaltarwasteproduct.Despitehisbestefforts,however,hedidnotendupwithquinine.Instead,heproducedamysteriousdarksludge.Luckily,Perkin’sscientifictrainingandnaturepromptedhimtoinvestigatethesubstancefurther.Incorporatingpotassiumdichromateandalcoholintotheanilineatvariousstagesoftheexperimentalprocess,hefinallyproducedadeeppurplesolution.And,providingthetruthofthefamousscientistLouisPasteur’swords‘chancefavoursonlythepreparedmind’,Perkinsawthepotentialofhisunexpectedfind.Historically,textiledyesweremadefromsuchnaturalsourcesasplantsandanimalexcretions.Someofthese,suchastheglandularmucusofsnails,weredifficulttoobtainandoutrageouslyexpensive.Indeed,thepurplecoulourextractedfromasnailwasoncesocostlythatinsocietyatthetimeonlytherichcouldaffordit.Further,naturaldyestendedtomemuddyinhueandfadequickly.ItwasagainstthisbackdropthatPerkin’sdiscoverywasmade.Perkinquicklygraspedthathispurplesolutioncouldbeusedtocolourfabric,thusmakingittheworld’sfirstsyntheticdye.Realizingtheimportanceofthisbreakthrough,helostnotimeinpatentingit.ButperhapsthemostfascinatingofallPerkin’sreactionstohisfindwashisnearlyinstantrecognitionthatthenewdyehadcommercialpossibilities.PerkinoriginallynamedhisdyeTyrianPurple,butitlaterbecamecommonlyknownasmauve(fromtheFrenchfortheplantusedtomakethecolourviolet).HeaskedadviceofScottishdyeworksownerRobertPullar,whoassuredhimthatmanufacturingthedyewouldbewellworthitifthecoulourremainedfast(i.e.wouldnotfade)andthecostwasrelativelylow.So,overthefierceobjectionsofhismentorHofmann,heleftcollegetogivebirthtothemodernchemicalindustry.Withthehelpofhisfatherandbrother,PerkinsetupafactorynotfarfromLondon.UtilisingthecheapandplentifulcoaltarthatwasanalmostunlimitedbyproductofLondon’sgasstreetlighting,thedyeworksbeganproducingtheworld’sfirstsyntheticallydyedmaterialin1857.ThecompanyreceivedacommercialboostformtheEmpressEugenieofFrance,whenshedecidedthenewcolourflatteredher.Verysoon,mauvewasthenecessaryshadeforallthefashionableladiesinthatcountry.Nottobeoutdone,England’sQueenVictoriaalsoappearedinpublicwearingamauvegown,thusmakingitalltherageinEnglandaswell.Thedyewasboldandfast,andthepublicclamouredformore.Perkinwentbacktothedrawingboard.AlthoughPerkin’sfamewasachievedandfortuneassuredbyhisfirstdiscovery,thechemistcontinuedhisresearch.Amongotherdyeshedevelopedandintroducedwereanilinered(1859)andanilineblack(1863)and,inthelate1860s,Perkin’sgreen.ItisimportanttonotethatPerkin’ssyntheticdyediscoverieshadoutcomesfarbeyondthemerelydecorative.Thedyesalsobecamevitaltomedicalresearchinmanyways.Forinstance,theywereusedtostainpreviouslyinvisiblemicrobesandbacteria,allowingresearcherstoidentifysuchbacilliastuberculosis,cholera,andanthrax.Artificialdyescontinuetoplayacrucialroletoday.And,inwhatwouldhavebeenparticularlypleasingtoPerkin,theircurrentuseisinthesearchforavaccineagainstmalaria.ReadingPassage2IsThereAnybodyOutThere?TheSearchforExtra-terrestrialIntelligenceThequestionofwhetherwearealoneintheUniverseuni(一)+vers(转)+ehashauntedhunt-haunt;h(home)+aunt大姨妈来家里humanityhuman+i+ty.hum(潮湿/泥土/人)+anforcenturies,butwemaynowstandpoisedpoise=pois(悬放)+e。pend/pens/pent(悬)frompos(放)(悬着,平衡,泰然镇静)onthebrinkoftheanswertothatquestion,aswesearchforradiosignalssign四个牛。sign(签/标注)+al(形缀/名缀)fromotherintelligentintelligent=inter(之间uni(一)+vers(转)+ehunt-haunt;h(home)+aunt大姨妈来家里human+i+ty.hum(潮湿/泥土/人)+anpoise=pois(悬放)+e。pend/pens/pent(悬)frompos(放)sign四个牛。sign(签/标注)+al(形缀/名缀)intelligent=inter(之间)+lig(leg/lect选)+ent。ent=ant,ence=ance,ency=ancy智能旳civil(民事旳,公民旳。civilwar内战)+iz(e)(动缀)+a+tion。文明,文化acro(高/顶/首。杂技旳代称acrobatics在高处行走)+nym(=name。anonymous匿名旳)terrestrial=terra(地球,大地)+e+str(=st站立,伫立)+al地球旳,陆地旳inter(之间between)+mitt(=mit投射)+ent,间歇旳,断续旳techn(=tech科技。hi-tech高科技)+o+logy(学问)。科技axx+tempt(得罪宙斯旳国王,被宙斯困入水中,食物近在嘴边,却吃不到。努力争取,尝试)尝试,试图。temptation诱惑物,引诱。ATheprimaryreasonforthesearchisbasiccuriosity–thesamecuriosityaboutthenaturalworldthatdrivesallpurescience.WewanttoknowwhetherwearealoneintheUniverse.Wewanttoknowwhetherlifeevolvesnaturallyifgiventherightconditions,orwhetherthereissomethingveryspecialabouttheEarthtohavefosteredthevarietyoflifeformsthatweseearoundusontheplanet.Thesimpledetectionofaradiosignalwillbesufficienttoanswerthismostbasicofallquestions.Inthissense,SETIisanothercoginthemachineryofpuresciencewhichiscontinuallypushingoutthehorizonofourknowledge.However,thereareotherreasonsforbeinginterestedinwhetherlifeexistselsewhere.Forexample,wehavehadcivilizationonEarthforperhapsonlyafewthousandyears,andthethreatsofnuclearwarandpollutionoverthelastfewdecadeshavetoldusthatoursurvivalmaybetenuous.Willwelastanothertwothousandyearsorwillwewipeourselvesout?Sincethelifetimeofaplanetlikeoursisseveralbillionyears,wecanexpectthat,ifothercivilizationsdosurviveinourgalaxy,theirageswillrangefromzerotoseveralbillionyears.Thusanyothercivilizationthatwehearfromislikelytobefarolder,onaverage,thanourselves.Themereexistenceofsuchacivilizationwilltellusthattheoldercivilizationmaypassonthebenefitsoftheirexperienceindealingwiththreatstosurvivalsuchasnuclearwarandglobalpollution,andotherthreatsthatwehaven'tyetdiscovered.BIndiscussingwhetherwearealone,mostSETIscientistsadopttwogroundrules.First,UFOs(UnidentifiedFlyingObjects)aregenerallyignoredsincemostscientistsdon’tconsidertheevidenceforthemtobestrongenoughtobearseriousconsideration(althoughitisalsoimportanttokeepanopenmindincaseanyreallyconvincingevidenceemergesinthefuture).Second,wemakeaveryconservativeassumptionthatwearelookingforalifeformthatisprettywelllikeus,sinceifitdiffersradicallyfromuswemaywellnotrecognizeitasalifeform,quiteapartfromwhetherweareabletocommunicatewithit.Inotherwords,thelifeformwearelookingformaywellhavetwogreenheadsandsevenfingers,butitwillneverthelessresembleusinthatitshouldcommunicatewithitsfellows,beinterestedintheUniverse,liveonaplanetorbitingastarlikeourSun,andperhapsmostrestrictively,haveachemistry,likeus,basedoncarbonandwater.CEverwhenwemaketheseassumptions,ourunderstandingofotherlifeformsisstillseverelylimited.Wedonotevenknow,forexample,howmanystarshaveplanets,andwecertainlydonotknowhowlikelyitisthatlifewillarisenaturally,giventherightconditions.However,whenwelookatthe100billionstarsinourgalaxy(theMilkyWay),and100billiongalaxiesintheobservableUniverse,itseemsinconceivablethatatleastoneoftheseplanetsdoesnothavealifeformonit;infact,thebesteducatedguesswecanmake,usingthelittlethatwedoknowabouttheconditionsforcarbon-basedlife,leadsustoestimatethatperhapsonein100,000starsmighthavealife-bearingplanetorbitingit.Thatmeansthatournearestneighboursareperhaps100lightyearsaway,whichisalmostnextdoorinastronomicalterms.DAnaliencivilizationcouldchoosemanydifferentwaysofsendinginformationacrossthegalaxy,butmanyoftheseeitherrequiretoomuchenergy,orelseareseverelyattenuatedwhiletraversingthevastdistancesacrossthegalaxy.Itturnsoutthat,foragivenamountoftransmittedpower,radiowavesinthefrequencyrange1000to3000MHztravelthegreatestdistance,andsoallsearchestodatehaveconcentratedonlookingforradiowavesinthisfrequencyrange.Sofartherehavebeenanumberofsearchesbyvariousgroupsaroundtheworld,includingAustraliansearchesusingtheradiotelescopeatParkes,NewSouthWales.Untilnowtherehavenotbeenanydetectionsfromthefewhundredstarswhichhavebeensearched.Thescaleofthesearcheshasbeenincreaseddramaticallysince1992,whentheUSCongressvotedNASA$10millionperyearfortenyearstoconductathoroughsearchforextra-terrestriallife.Muchofthemoneyinthisprojectisbeingspentondevelopingthespecialhardwareneededtosearchmanyfrequenciesatonce.Theprojecthastwoparts.Onepartisatargetedsearchusingtheworld’slargestradiotelescopes,theAmerican-operatedtelescopeinArecibo,PuertoRicoandtheFrenchtelescopeinNancyinFrance.Thispartoftheprojectissearchingthenearest1000likelystarswithhighsensitivityforsignalsinthefrequencyrange1000to3000MHz.Theotherpartoftheprojectisanundirectedsearchwhichismonitoringallofspacewithalowersensitivity,usingthesmallerantennasofNASA’sDeepSpaceNetwork.EThereisconsiderabledebateoverhowweshouldreactifwedetectasignalfromanaliencivilization.Everybodyagreesthatweshouldnotreplyimmediately.Quiteapartformtheimpracticalityofsendingareplyoversuchlargedistancesatshortnotice,itraisesahostofethicalquestionsthatwouldhavetobeaddressedbytheglobalcommunitybeforeanyreplycouldbesent.Wouldthehumanracefacethecultureshockiffacedwithasuperiorandmucholdercivilisaiton?Luckily,thereisnoturgencyaboutthis.Thestarsbeingsearchedarehundredsoflightyearsaway,soittakeshundredsofyearsfortheirsignaltoreachus,andafurtherfewhundredyearsforourreplytoreachthem.It’snotimportant,then,ifthere’sadelayofafewyears,ordecades,whilethehumanracedebatesthequestionofwhethertoreplay,andperhapscarefullydraftsareply.ReadingPassage3ThehistoryoftheTortoise RichardDawkins,TheGuardian,Saturday26February。InthesecondofthreeessayswrittenonarecentvisittotheGalápagosIslands,RichardDawkinsconsidersanotheroftheextraordinarycreaturesthathelpedinspireDarwin'

温馨提示

  • 1. 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。图纸软件为CAD,CAXA,PROE,UG,SolidWorks等.压缩文件请下载最新的WinRAR软件解压。
  • 2. 本站的文档不包含任何第三方提供的附件图纸等,如果需要附件,请联系上传者。文件的所有权益归上传用户所有。
  • 3. 本站RAR压缩包中若带图纸,网页内容里面会有图纸预览,若没有图纸预览就没有图纸。
  • 4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
  • 5. 人人文库网仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对用户上传分享的文档内容本身不做任何修改或编辑,并不能对任何下载内容负责。
  • 6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
  • 7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。

评论

0/150

提交评论