398 



THE GUIDE TO NATURE 



The Heavens for May. 



BY PROF. ERIC DOOLITTLE OF THE UNI- 

 VERSITY OF PENNSYLVANIA. 



High above the Virgin there shines 

 the constellation of Bootes, or the 

 Driver, whose brightest star, Arcturus, 

 is a wonderful object. A study of the 

 light of this golden-yellow star shows 



that its distance cannot be measured 

 by any means which we at present pos- 

 sess. We know, however, that its light 

 requires at least ioo, and probably 200 

 or 300, years to come to us, and that it 

 is many thousands of times brighter 

 than our own sun. Could our sun be 

 removed into the depths of space and 



NORTH 



South 



Figure 1. The Constellations on May 1, at 9 P.M. (If facing south hold the map upright. If facing north 

 hold the map inverted. If facing east hold "East" below; if facing west hold "West'' below.) 



us that it is a sun in very nearly the 

 same condition as our own sun, but al- 

 most inconceivably larger and brighter. 

 For the apparent brillance of Arcturus 

 does not arise from its nearness to us; 

 in fact, this star is so very far away 



placed beside Arcturus, it would appear 

 to us as a faint, tenth-magnitude star. 

 There are no less than seven of the 

 brightest stars of the sky which are 

 so far away from us that their distance 

 cannot be measured. One of these is 



