278 ELEMENTS OF GENERAL SCIENCE 



Vega will move over to the position that the Pole Star now 

 occupies, but that the axis of the earth will change until it 

 points in the direction of Vega. This change is produced by 

 the attraction of the sun and moon for the equatorial bulge 

 of the earth. Nor will Vega be permanently the Pole Star, 

 for the position of the earth's axis changes continually, com- 

 pleting a circle in the heavens in about twenty-six thousand 

 years. 



Just west of Lyra is the large constellation Hercules, 

 the Kneeling Hero. It contains no bright stars. In the 

 south, and a little to the west of the meridian, is one of the 

 faintest groups of stars in the whole sky. This is Scorpio, 

 the Scorpion. It can always be recognized by its fiery- 

 red, first-magnitude star Antares, which in light-giving power 

 is several hundred times greater than the sun. Antares is 

 represented in mythology as occupying the position of the 

 heart of the great scorpion. According to a Greek legend 

 Scorpio is the monster that killed Orion and frightened the 

 horses of the sun so that Phaethon was thrown from his 

 chariot when he attempted to drive them. 



279. The Milky Way, or Galaxy. Everyone has observed 

 the great band of stars which extends across the entire sky 

 and is known as the Milky Way (fig. 135) because its stars 

 are so thick as to give the appearance of an immense stream 

 of milk. The hundreds of millions of stars are grouped more 

 or less definitely into aggregations or constellations. There 

 are probably at least 500,000,000 of them, and all together 

 they are known as the Galaxy. The sun at the present 

 time is somewhere in the interior of the Galaxy. 



