MIRACLES OF SCIENCE 



star clusters or world systems. Very recently, to be 

 sure, the question has been raised as to whether some 

 nebulae may not be in reality veritable universes of 

 stars, lying far beyond the limits of our sidereal sys- 

 tem, as was formerly supposed. But there are cases 

 in which no such interpretation can be put upon the 

 observed conditions; cases in which the process of 

 star-formation seems to be directly revealed in a great 

 modern telescope. 



In the group of the Pleiades, familiarly known as 

 the "little dipper," for example, such a process of star- 

 formation may be clearly observed. To the naked eye 

 and even to a telescope of considerable power, the 

 main stars of this group (those that outline the dip- 

 per) appear as ordinary stars of the fifth or sixth 

 magnitude. But in the great five-foot Mt. Wilson 

 reflector, these stars seem to be surrounded by a 

 misty veil of nebulous matter. In photographs of 

 long exposure, shreds of the nebulous matter are seen 

 to extend from one star to another. They leave no 

 doubt that the divers stars are enmeshed in the same 

 nebulous structure. 



Here, then, we observe the later stages of develop- 

 ment of nebular condensation; or, from the other 

 point of view, the earlier stages of star-formation. 

 Could we look ahead sundry millions of years, we 

 should doubtless see the stars of the Pleiades shining 

 as clear central points without a nimbus, each one 

 having absorbed (through gravitation) the nebular 

 matter that now surrounds it. 



There is every reason to believe that numberless 

 star groups in the heavens have had a similar origin. 



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