SAT 



Inside diameter smaller ring- 146345 



Outside do 18439S 



Inside diameter larger ring 190246 



Outside do 201883 



Breadth of inner ring 20000 



i of outer ring 7200 



Space between rings 2839 



between planet and ring 70277 



Mean thickness of ring 4500 



Time of rotation 107*. 32m. 15,4s. 



When Saturn's geocentric longitude is 5*. 20. or Us. 20, his ring is 

 invisible to us. When he is in 2*. 20. or 8*. 20. we may see it to most 

 advantage ; its minor axis is then nearly half its major. But the fol- 

 lowing Table will shew both the apparent figure of the ring, and of the 

 orbits of the six first satellites, at all times, and as seen either from the 

 sun or the earth. 



N.B. When the geocentric latitude and longitude are taken, we get 

 the appearance as seen from the earth ; the heliocentric latitude and 

 longitude being assumed, gives the appearance as seen from the sun. 



To the quantity taken from 

 the Tables, apply the latitude 

 of Saturn expressed in minutes 

 divided by 4000, with the sign 

 , when the latitude is north, 

 and +, when it is south ; and 

 the result gives the minor axis 

 of the ring or of the orbits, the 

 major axis being unity. 



-Ex. On April 22, 1767, the geocentric latitude of Saturn was 1. 10' 

 gouth, and longitude 2*. 1C . 55'; hence for the ring and six first satel- 

 lites. 



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