WPC  ,n8Ҹ0}[2,Ey2^Gu)Kl1ƝJ "Véxc@IsͮM!vֻ +ⷅOɶJiCfK2e,G!&Y7Scʢ3,O[RɃ}?zv|IWݯ24OBE~ǒ‘Ql; 5h3ƉNϑA "0Ӌ6қF#.[X`ذM\JfB{y)k!9c.I!-ʤ2%P7j2@C:a_)\z|6Fo5H+x[ךؠ̬֘"bO~o:#1fY C`ͪqh]U)H&ıeW/QcLgU: %U@ 0I" Ckkk B * B 0#!l N UN ^ w@ 4) = m? fV aX X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X D3l l l l l l l l l l l l l D3 <6X9`("Courier 10cpiX* `(CG TimesScalable4 2Quick 1..0.. d&0 d d d#|w (hu$   XXXXXXXXXHP LaserJet 6P/6MP - Enhanced0(uH Z6Times New Roman RegularrX, EEEEt\$,:i+00UTABLE A 'dxd'dxd  u!   XX֗XXXXeXXX֗  _   XdXXXeNAME__________________________________      GALILEOANDTHEMOONSOFJUPITER  b     1.0  In1610AD,GalileobegansystematicobservationsoftheplanetJupiter,andnoticedthatthe  d planetwasattendedby starswhichseemedtochangepositionduringthenight. (#(# ' ,0  Accordingly,ontheseventhdayofJanuaryofthepresentyear1610,atthefirsthourofthenight,whenIinspectedthecelestialconstellationsthroughaspyglass,Jupiterpresentedhimself.AndsinceIhadpreparedformyselfasuperlativeinstrument,Isaw(whichearlierhadnothappenedbecauseoftheweaknessoftheearlierinstruments)thatthreelittlestarswerepositionednearhimsmallbutyetverybright.AlthoughIbelievedthemtobeamongthenumberoffixedstars,theyneverthelessintriguedmebecausetheyappearedtobearrangedexactlyalongastraightlineandparalleltotheecliptic,andtobebrighterthanothersofequalsize.1`!! ' X0  NoticethatGalileowasclevertonoticethestars'alignmentwiththeecliptic.GalileocontinuedhisobservationsofJupiteranditsmoons,reportingtheobservationsanddrawingsinhis_Sidereus_  _Nuncius_,orSiderealMessenger,in1610.(#(# OnthelastpageofthisexperimentisareproductionofdrawingsGalileomadein1610,showingJupiterasanopencircle,anditssatellitesasstarsnearby.WewilluseStarryNighttodeterminethecircumstancesofGalileo'sobservationsandtoinvestigatethem. 2.0  UsingLocationintheToolBar,setthelongitudeto16degreesandEforEast(approximate B locationintheVenetianRepublic),changethetimezoneto+1hour,thenSetLocation.ChangethedatetoJanuary7,1610,andthetimeto5:30_pm_.Noticethatthisistheapproximatetimeofdusk.Therefore,referringtoGalileosfirstsentenceabove,the firsthourofthenightwasmostprobably6:30_pm_.SetstarryNightfor6:30_pm_.,thenchooseanequatorialorientation. (#(# 0   (#(# 3.0  Find,then_Centre_/lockonJupiter.Changethefieldofviewto30'.Comparethecomputer <#" simulationtoGalileo'sdrawing,andcommentontheaccuracyofthedrawing.WhydoyousupposeTthatIoandEuropaaredepictedbyGalileoasoneobject?(Hint,squintatthescreen). (#(#  ,10  _Sidereus_Ԁ_Nuncius_ԀorTheSiderealMessenger,Galileo_Galilei_,atranslationbyAlbertVan_Helden_, 8,', UniversityofChicagoPress,Chicago.1987-n(-(#(#  4.0  StepaheadonedaytoJanuary8.ComparethecomputersimulationagaintoGalileo'ssecondthird b drawing,andspeculateonwhyGalileodidnotdepict_Callisto_. (#(# 5.0  StepaheadtwodaystoJanuary10.NoticeagainthatGanymedeandEuropaaredepictedasone *z  object. (#(# 0  StepaheadonedaytoJanuary11.SpeculateonwhyGalileodidnotdepictIoandEuropa. (#(# 0  ItishereinGalileosseriesofobservationsthathemakesthefollowingbrilliantconclusion. (#(# ! ,,!0  0!! Ithereforearrivedattheconclusion,entirelybeyonddoubt,thatintheheavenstherearethreestarswanderingaroundJupiterlikeVenusandMercuryaroundtheSun. !! 0  GalileosobservationsshowedthatitwasthereforepossiblefortheMoonto wanderaroundtheEarth.The_geocentrists_ԀhadarguedthattheEarthmustbeatthecenterofthesolarsystem,forifinsteaditmovedaroundtheSun,theEarthwouldleavetheMoonbehind.ButhereisJupitermanagingtohangontoitsmoons. (#(# 6.0  StepaheadtwodaystoJanuary13.NoticethathereforthefirsttimeGalileoseesfourmoons.<#"(#(#   %X $ AlthoughitisbelievedthatGalileoknewof_Kepler_'sworkinastronomy,thereisnoevidencethatGalileoapplied_Kepler_'sHarmonicLawtothefourmoonsorbitingJupitertoseeifthey,liketheplanetsorbitingtheSun,obeyedthelaw.Letusinvestigate.7.0  UseSkyandturnoffthedaylight.Rightclickon_Callisto_,thenchooseShoworbit.Measurethe  0 diameterof_Callisto_sorbit,estimatingtothenearestmm.RecordthisintheTable. (#(# 0  Gobackwardintimeafewhourstoplace_Callisto_Ԁneartheedge(limb)ofJupiter.theJupiter,andrecordtheJuliandateintheTable.BringtheTimeToolsleftedgeto_Callisto_,makingastart/finishlineJupiter,andrecordtheJuliandateintheTable..Thenmoveforwardintimebyhoursuntil_Callisto_ԀhasexecutedonefullorbitaroundJupiter.RecordtheJuliandatewhen_Callisto_Ԁrearrivesbackatatthestart/finishline.\.ThenfromthedifferencebetweenthetwoJuliandates,computetheorbitalperiodindaysandrecordthatintheTable. (#(# 8.0  RepeatthisproceduretofindthesizesandperiodsforGanymede,Europa,andIo.(#(# 9.0  Lastly,entertheseorbitalperiodsandtheorbitaldiametersintothegraphingprogram,andsearch t forarelationshipbetweenthem. (#(# *f ddd Xdd Xdd X(#(#_,dd ,dd ,dd ,dd ,dd +   B  4#V 4Callisto =,!V" =Ganymede =,!V" =Europa =,!V" =Io -#!V " -OrbitalDiameter,mm   !    "    #    $    % StartJD  J &   J '   J (   J )   J * EndJD  !+   !,   !-   !.   !/ Period,days  >#0   >#1   >#2   >#3  >#4  ``;(#,,XXd, ,,,r,, 225February2002#, ,r #XeX,,