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ANNUAL REPORT SMITHSONIAN INSTITUTION, 1932 



It is clear that eclipsing stars constitute a very special selection 

 among double stars: They are those systems where one star passes 

 in front of the other and cuts off a, part or all of its light, in much 

 the same way that the moon cuts off the light of the sun when a solar 



Taurus 



Auriga 



Sagittarius 



scorpius 



FiGDRE 3. — Distribution of globular clusters 

 Plane of paper is plane of milky way ; large concentric circles represent distances 

 from sun (at center of diagram), the unit being 25,000 light-years; the center of 

 the milky way system is represented by a cross. Small circles represent globular 

 clusters ; farthest cluster is too far away to appear on the diagram. 



eclipse occurs. They constitute only a part of those close doubles 

 which to the unaided eye or in the telescope appear as single stars. 

 There are other systems whose components revolve in planes so 

 oriented relative to the line of sight that no eclipse can occur. These 

 are the spectroscopic binaries, the duplicity of which is revealed from 



