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Show Clusters lusters o oWhirl of f Stars StarsWhirl tars Whirl About Other OtherCelestial OtherCelestial Celestial GroupsNew Groups GroupsNew New Discoveries Show ShowMilky ShowMilky Milky Way's Ways ' StructureCambridge Structure StructureCambridge Cambridge , MassImpor Mass -Impor- Impor - Important Important Impor Important - - tant new clues to the struc struc- structure struc- struc structure structure - - ture of the Milky Mllky Way have havebeen havebeen havebeen been found at the Harvard Harvardobservatory Harvardobservatory Harvardobservatory observatory where officials officialsannounced officialsannounced officialsannounced announced discovery of a anew anew anew sub sub- subsystCln subsystem subsystem new type of astronomical - system systCln in m the universe uruverse . The new system consists of a gI- gI gIant giant gi giant - - ant cluster of some hundreds of ofstars ofstars ofstars stars which revolves about a still stilllarger stilllarger stilllarger larger cluster , much as the earth earthtravels earthtravels earthtravels travels about the sun Astronomers Astronomershere Astronomershere Astronomershere here say it presents the first posi POSI- POSItive posi- posi positive positive - - tive indication mdlcatlon they have had that thatthese thatthese thatthese these tremendous clusters may 1R lid : ! lidconnected tieconnected connected with ono ona one another by grav grav- gravIty gravity gravity - ity to form independent sub orders orderswlthm orderswithin orderswithin wlthm within the galaxy . The discovery , made by James JamesCufIey JamesCuffey JamesCuffey CufIey Cuffey of the Harvard observatory observatorystaff observatorystaff observatorystaff staff , was the result of numerous numerousextremely numerousextremely numerousextremely extremely accurate computations of ofthe ofthe ofthe the distances from the sun of nme nmegalactlc nmegalactic ninegalactic galactlc galactic star clusters in the constel constel- constellation constellation constellation - - lation Amiga Auuga Auriga , , the most comprehen comprehen- comprehensive comprehensive comprehensive - - sive and exact measurements of ofthese ofthese ofthese these distances ever made . The two clusters the research researchshowed researchshowed researchshowed showed to be companions compamons are those thoseknown thoseknown thoseknown known as Messier 38 3B 36 , which has a amass amass amass mass about 500 times bmes that of our oursun oursun oursun sun , and NGC 1907 , which is about about75 75 times bmes the mass of the sun The Thesmaller Thesmaller Thesmaller smaller one , it was found , revoh revolt revohesabout es esabout esabout about the larger cluster with the thetlme thetime thetime tlme time required for one complete rev rev- revolution revolution revolution - olution es estimated mated to be about 60,000- 60,000 60000 60,000000 60,000000 60,000-000 60,000 60000 000 , , - 000 years yenrs . Colors Determine Dctcrmme Distances . A painstaking pamstakmg study of the colors colorsof colorsof colorsof of nine rune such groups m in Auriga led to tothe tothe tothe the conclusion that these two clus clus- clusters clusters clusters - ters constitute a system The col col- colors col- col colors colors - - ors of stars in m clusters are used by byastronomers byastronomers byastronomers astronomers to determine determme their dlS- dlS dis- dis dlSances distances dis distances - - tances tances ances and Messier MeSSler 38 and NGC 1907 1907were 1907were 1907were were found to have very similar similarcharacterIstics similarcharacteristics similarcharacteristics characterIstics Thus they were wereshown wereshown wereshown shown to be about the same dJs- dJs dis- dis dJstance distance dis distance - - tance from the sun , appro approi.irnately approiirnately approximately28,000 approximately28000 .unately unately > . . 28,000 28000 , light lJght years In space they theyare theyare theyare are only 24 light years apart . . A third thlrd and still larger cluster clusterMessier , Messler Messier 36 , , Is also believed bel1eved to be bephysIcally bephysically bephysically physIcally connected with the othertwo othertwo other 'two two ' two groups for it too is about 28,000 28000 28,000hght 28,000light 28,000light 28000light , hght light years from the sun It IS ISabout isabout isabout about 150 light years from the first firsttwo firsttwo firsttwo firsttwoMr two twoMr Mr . Cufley Cuffey doubts , however , tlJat that tlJatthere thatthere thatthere there is any possibility posslbll1ty of a second secondrotation secondrotation secondrotation rotation , of the pair around Messier Messier36 36 as a common center of gravIty gravityfor , for dynamical reasons Four oth other otherclusters otherclusters r rclusters clusters in 10 Auriga which Mr Cuffey CuffeystudIed Cuffeystudied CufTeystudied studIed appear close together togetherhenviewed when whenvietied . \\henviewed henviewed \ \ hen henvleled vle\led vle led vietied \ from the earth but are aremerely aremerely aremerely merely an optical optlcal group rather thn thin thina thna , a physically physlcall } connected system , he hehas hehas hehas has decided T Two THo , o of them are at atan atan atan an equal distance from the sun but butanother butanother butanother another is more than four times bmes as asfar asfar asfar far while the last is hardly half as asdistant asdistant asdistant distant . . |