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other snuilar siars^ ot balls beyond the ones wLicIi we 

 see^ but they are not visible except through the tele- 

 scope, and it is believed that there are still others be- 

 yond these. All a£ these bodies do not shine by their 

 own light. Those nearest the earth shine by the light 

 of the sun, and are called planets^ and move with the 

 earth around the sun. Some of these planets have 

 moons or satellites moving around them. These are 

 also included in the Solar System. Think of our earth 

 resting upon nothing, and turning rapidly in rotation, 

 which if it were not for friction and gravitation would 

 hurl everything from its surface. It also has another 

 motion called revolution, Tliis is its traveling around 

 the sun. The eight planets are named in order^ accord- 

 ing to their distance from the sun. Mercury is the 

 nearest, then comes Venus, then the Earthy then Mars, 

 Jupiter, Saturn, Uranus and Neptune. The J&rst four 

 are comparatively small while the last four are compar- 

 atively large, Jupiter being nearly fourteen-hnndred 

 times larger than the earth. Saturn has besides its 

 moons a number of ring-like accumulations of matter 

 revohnng around it. The sun is the central body of 

 the Solar System, and from it proceeds the light we 

 see and the heat we feel. The heat of the sun is be- 

 lieved to be caused by the contraction of the burning 

 mass which forms it. Comets are star-like bodies hav- 

 ing a train of shining light called a tail. They revolve 

 in or through an elliptical orbit, and are very beautiful. 

 Meteors are bodies or stars which fall from their posi- 

 tion. Many times when viewing the stars, you notice 

 one of their number fall or shoot some distance and 

 then disappear; and quite frequently stars leave a show- 



