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1、2010年职称英语理工类A级真题答案及解析第四部分阅读理解HowtheFirstStarsintheUniverseCameintoExistence ResearchersbelievethatouruniversebeganwiththeBigBangabout13billionyearsago,.Andthatsoonafterthatevent,matterbegantoformassmalldustgrainsandgases.Howthefirststarsformedfromthisdustandgashasbeenaburningquestionfory
2、ears,butastate-of-the-artcomputersimulationnowoffersthemostdetailedpictureyetofhowthesefirststarsintheuniversecameintoexistence. Thecompositionoftheearlyuniversewasquitedifferentfromthatoftoday,andthephysicsthatgovernedtheearlyuniversewerealsosomewhatsimpler.Dr.NaokiYoshidaandcolleaguesi
3、nJapanandtheU,S.incorporatedtheseconditionsoftheearlyuniverse,sometimesreferredtoasthe"cosmicdarkages,"tosimulatetheformationofanastronomicalobjectthatwouldeventuallyshineitslightintothisdarkness. Theresultisadetaileddescriptionoftheformationofaprotostar-theearlystageofamassiveprimordial
4、starofouruniverse--andtheresearchers'computersimulationsetsthebarforfurtherinvestigationintothestarformationprocess.Thequestionofhowthefirststarsevolvedissoimportantbecausetheirformationsandeventualexplosionsprovidedtheseedsforsubsequentstarstocomeintobeing. Accordingtotheirsimulation,gr
5、avityactedonminutedensityvariationsinmatter,gases,andthemysterious"darkmatter"oftheuniverseaftertheBigBanginordertoformthisearlystage,ofastar—aprotostarwithamassofjustonepercentofoursun.Thesimulationrevealshowpre-stellargaseswouldhaveactuallyevolvedunderthesimplerphysicsoftheearlyuniverse
6、toformthisprotostar.Dr.Yoshida'ssimulationalsoshowsthattheprotostarwouldlikelyevolveintoamassivestarcapableofsynthesizingheavyelements,notjustinlatergenerationsofstars,butsoonaftertheBigBang. "Thisgeneralpictureofstarformation,andtheabilitytocomparehowstellarobjectsformindifferenttimeper
7、iodsandregionsoftheuniverse,willeventuallyallowinvestigationintotheoriginsoflifeandplanets,"saidLarsHernquist,aProfessorofAstronomyatHarvardUniversity."Theabundanceofelementsintheuniversehasincreasedasstarshaveaccumulated,"hesays,"andtheformationanddestructionofstar
