THE SOLAR SYSTEM 



Long ago Syrian shepherds, keeping watch over 

 their sheep in the quiet of the night, used to gaze at 

 the myriads of stars that twinkled down upon them 

 with a friendly light. They loved these stars as if 

 they were friends, for they were the only companions 

 the lonely shepherds had during those long, dark 

 nights. They had noticed the way the stars are 

 grouped in constellations, and they watched from 

 night to night to see when the same group of stars 

 would come above the horizon and swing up into the 

 sky. To some of the brightest stars they gave names, 

 and they learned just when and where to look for 

 them, and for the constellations of which they made 

 a part. 



Among the brighter stars they had observed some 

 that were not always to be found when looked for. 

 These changed their places from time to time, and 

 did not seem to stay long with the same set of com- 

 panion stars. So they called them planets, which 

 meant wanderers. 



For a long time men did not know what the planets 

 were, or why they acted in such a different way from 

 the other stars. Still less did they suspect that our 

 earth, on which we live, is just another one of these 

 planets. But we know now that the planets are 

 worlds, as is our earth, and shine by reflected hght like 



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