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职称英语学习：http://edu.21cn.com/kcnet470/2012职称英语考试理工类A级真题第一篇SmallButWise【小而聪明】OnDecember14,NASA1blastedasmallbutmightytelescopeintospace.ThetelescopeiscalledWISEandisaboutaswidearoundasatrashcan.Don'tletitssmallsizefoolyou:WISEhasapowerfuldigitalcamera,anditwillbetakingpicturesofsomethewildestobjects2intheknownuniverse,includingasteroids,faintstars,blazinggalaxies3andgiantcloudsofdustwhereplanetsandstarsarebom.“I'mveryexcitedbecausewe'regoingtobeseeingpartsoftheuniversethatwehaven'tseenbefore,”saidNedWright,ascientistwhodirectstheWISEproject.Sincearrivinginspace,theWISEtelescopehasbeencirclingtheEarth,heldbygravityinapolarorbit4(thismeansitcrossesclosetothenorthandsouthpoleswitheachlap5).Itscameraispointedoutward,awayfromtheEarth,andWISEwillsnapapictureofadifferentpartoftheskyevery11minutes.Aftersixmonthsitwillhavetakenpicturesacrosstheentiresky.ThepicturestakenbyWISEwon'tbelikeeverydaydigitalphotographs,however.WISEstandsfor“Wide-fieldInfraredSurveyExplorer.”Asitsnamesuggests,theWISEcameratakespicturesoffeaturesthatgiveoffinfraredradiation6.Radiationisenergythattravelsasawave.Visiblelight,includingthefamiliarspectrumoflight7thatbecomesvisibleinarainbow,isanexampleofradiation.Whenanordinarydigitalcameratakesapictureofatree,forexample,itreceivesthewavesofvisiblelightthatarereflectedoffthetree.Whenthesewavesenterthecamerathroughthelens,they'reprocessedbythecamera,whichthenputstheimagetogether.Wavesofinfraredradiationarelongerthanwavesofvisiblelight,soordinarydigitalcamerasdon'tseethem,andneitherdotheeyesofhumanbeings.Althoughinvisibletotheeye,longerinfraredradiationcanbedetectedaswarmthbytheskin.That'sakeyideatowhyWISEwillbeabletoseethingsothertelescopescan't.Noteverythingintheuniverseshowsupinvisiblelight.Asteroids,forexample,aregiantrocksthatfloatthroughspace—buttheyabsorbmostofthelightthatreachesthem.Theydon'treflectlight,sothey'redifficulttosee.Buttheydogiveoffinfraredradiation,soaninfraredtelescopelikeWISEwillbeabletopro
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