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1、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,anditwillbetakingpicturesofsomethewild
2、estobjects2intheknownuniverse,includingasteroids,faintstars,blazinggalaxies3andgiantcloudsofdustwhereplanetsandstarsarebom. “I'mveryexcitedbecausewe'regoingtobeseeingpartsoftheuniversethatwehaven'tseenbefore,”saidNedWright,ascientistwhodirectstheWISEpro
3、ject. Sincearrivinginspace,theWISEtelescopehasbeencirclingtheEarth,heldbygravityinapolarorbit4(thismeansitcrossesclosetothenorthandsouthpoleswitheachlap5).Itscameraispointedoutward,awayfromtheEarth,andWISEwillsnapapictureofadifferentpartoftheskyevery11m
4、inutes.Aftersixmonthsitwillhavetakenpicturesacrosstheentiresky. ThepicturestakenbyWISEwon'tbelikeeverydaydigitalphotographs,however.WISEstandsfor“Wide-fieldInfraredSurveyExplorer.”Asitsnamesuggests,theWISEcameratakespicturesoffeaturesthatgiveoffinfrared
5、radiation6. Radiationisenergythattravelsasawave.Visiblelight,includingthefamiliarspectrumoflight7thatbecomesvisibleinarainbow,isanexampleofradiation.Whenanordinarydigitalcameratakesapictureofatree,forexample,itreceivesthewavesofvisiblelightthatarereflec
6、tedoffthetree.Whenthesewavesenterthecamerathroughthelens,they'reprocessedbythecamera,whichthenputstheimagetogether. Wavesofinfraredradiationarelongerthanwavesofvisiblelight,soordinarydigitalcamerasdon'tseethem,andneitherdotheeyesofhumanbeings.Althoughin
7、visibletotheeye,longerinfraredradiationcanbedetectedaswarmthbytheskin. That'sakeyideatowhyWISEwillbeabletoseethingsothertelescopescan't.Noteverythingintheuniverseshowsupinvisiblelight.Asteroids,forexample,aregiantrocksthatfloatthroughspace—buttheyabsorb
8、mostofthelightthatreachesthem.Theydon'treflectlight,sothey'redifficulttosee.Buttheydogiveoffinfraredradiation,soaninfraredtelescopelikeWISEwillbeabletoproduceimagesofthem.DuringitsmissionWISEwilltakepicturesofhundredsoftho