The Milky Way 



very small number of stars. The other, less 

 rigorous but applicable to the entire firmament, 

 enables us to measure the distance of the stars 

 according to their brightness. We are now in 

 a position to imagine a sort of model of the 

 universe, showing each star in its actual place. 

 If, placing ourselves outside of it, we looked 

 at this reduced model of our universe we would 

 see a kind of mist, consisting of separate bright 

 spots, and of very irregular density, but of a 

 clearly defined general form. Imagine a large 

 lens, encircled, at its broadest part, by two 

 rings slightly inclined to one another. We 

 know only the interior part of these rings, 

 which alone are accessible to our most powerful 

 optical instruments. The ^olar system is 

 situated within the lens, and though placed 

 in a region poor in stars it is nevertheless 

 surrounded by a multitude of them; it does 

 not, however, occupy the centre. 



If we now direct our attention to the interior 

 of this microcosm, to the brilliant point which 

 marks the place of the solar system, it will be 

 easy for us to understand the appearance of 

 the starry heavens seen from our earth. When 



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