THE STARRY HEAVENS FOR MAY 



405 



the Hunter sinks below the ground as if 

 still in fear. The three bright stars 

 which cross the body of the Scorpion 

 bear indeed some resemblance to the 

 Belt of Orion and are sometimes mis- 

 taken by very inexperienced observers 

 for this latter figure. Possibly it is the 

 relative positions of these two striking 

 groups which first suggested the legend 

 of Orion fleeing from his slayer. 



For many centuries the Scorpion was 

 an even more beautiful group, for it in- 

 cluded the bright stars at A and B, Fig- 

 ure 1, which were later formed into the 

 new constellation of the Balances. This 

 part of Scorpio was dedicated to Venus 

 while the eastern region was the House 

 of Mars — to the astrologers an accursed 

 constellation, the source of wars and 

 plagues. This too is probably the 

 ''Chambers of the South," referred to in 

 the book of Job. 



The southern claw at A, Figure 1, is 



this sun was the brightest star of the 

 whole constellation while now it is not 

 one-sixth part as bright as the beautiful 



Figure 2. The formation of a spectrum. 



Antares near-by. but whether one of 

 these stars has since been steadily grow- 

 ing brighter or the other fainter we do 

 not know. Neither at present shows 

 signs of variability. 



easily seen to be a wide double star, even 

 with a very small telescope, while the 

 star at B is very remarkable for having 

 a distinctly greenish color, a very rare 

 tint among stars. Twenty centuries ago 



Figure 3. The spectroscope of the observatory at Potsdam. 



At the point C, nearly midway be- 

 tween B and D, there is a rather faint 

 star which, like the well-known Demon 

 Star, Algol, is periodically eclipsed by a 

 dark companion which revolves about 



