EXPLORING THE GLORIES OF THE FIRMAMENT 



177 



THE RING NKBULA IN LYRA, TAKEN WITH THE 60-INCH MOUNT 

 WILSON TELESCOPE 



The power of the big telescopes is strikingly shown by this picture. With the naked eye 

 one cannot see this nebula, which is in the neighborhood of Vega (see chart on page 170). 

 A cube, whose sides equal the distance across this nebula, would occupy a space large enough 

 to provide room for hundreds of millions of solar systems like ours. 



Cygnus, the Swan, with Deneb as its 

 principal star. Deneb is so far away 

 that the light rays entering our eyes from 

 it this year left it during the reign of 

 Queen Elizabeth. It is driving through 

 space toward us at the rate of nearly two 

 thousand miles a minute, spectroscopic 

 advices say. 



Eastward from the Pole — about as far 

 from Polaris as the latter is above the 

 northern horizon — is Cassiopeia, the 

 Woman in the Chair. The major stars 

 of this constellation form a letter "W." 

 The star at the middle of the third stroke 



is a double, its two members revolving 

 around a common center of gravity in a 

 period of about two hundred years. If 

 either of them has a family of planets, 

 their system of day and night, as well as 

 their seasons, must be powerfully com- 

 plicated. 



Well down toward the eastern horizon 

 is the constellation Andromeda, the 

 Chained Woman. It contains no first- 

 magnitude stars, but has a line of stars 

 of the second magnitude extending from 

 the northeast tpj the southwest, by which 

 it can be located. About fifteen degrees 



