8 VIEW OF THE HEAVENS. [LeSSOH II. 



more*: after describing to you the sun, I shall 

 proceed to the rest in their order. 



* Since the commencement of the present century, four 

 other Planets have been discovered. 



The first of these was discovered on the 1st of January, 

 1801, by M. Piazzi, of Palermo : its mean distance from the 

 sun is not qtiite three times that of the earth (2.768): its 

 revolution is performed in four years, seven months, and ten 

 days; and its orbit is inclined to the ecliptic in an angle 

 of about lOf degrees. This planet is much less in size than 

 our moon : its discoverer has given it the name of Ceres, but 

 most astronomers call it by the name of Piazzi. 



The second was discovered on the 20th of March 1802, by 

 Dr. Olbers, of Bremen. Its distance from the sun, time of 

 revolution, and magnitude, are nearly the same as Piazzi's 

 planet; and the orbits of the two intersect each other; the 

 latter being inclined to the ecliptic in an angle of about 34^ 

 degrees. It is called by the names Pallas, and Olbers. 



The third was discovered on the 1st of September 1801, by 

 M. Harding, of Lilienthal. Its mean distance from the sun 

 is rather greater than that of the two former; and its size 

 nearly equal to that of Ceres. Its inclination is 13 degrees. 

 It appears like a star of the eighth magnitude. Harding has 

 given to this planet the name of Juno. 



The- fourth was discovered by Dr. Olbers, early in 1807. 

 It is nearer to Mars than either of the other newly discovered 

 planets, its mean distance being rather more than 2| times 

 that of the earth ; and the revolution through its orbit is 

 performed in 1130 of our days. The inclination of that orbit 

 to the ecliptic is 7 and l-7th degrees, being rather more than 

 that of Mercury. The size of this planet is not known. 

 Astronomers have given it the name of Vesta. 



LESSON 



