240 HISTORY OF PHYSICAL ASTRONOMY. 



Virgo. He found a star which had a perceptible 

 motion even in the space of two hours. It was 

 soon announced as a new planet, and received from 

 its discoverer the name of Pallas. As in the case 

 of Ceres, Burckhardt and Gauss employed them- 

 selves in calculating its orbit. But some peculiar 

 difficulties here occurred. Its eccentricity is greater 

 than that of any of the old planets, and the incli- 

 nation of its orbit to the ecliptic is not less than 

 thirty-five degrees. These circumstances both made 

 its perturbations large, and rendered them difficult 

 to calculate. Burckhardt employed the known 

 processes of analysis, but they were found insuf- 

 ficient : and the Imperial Institute (as the French 

 Academy was termed during the reign of Napo- 

 leon,) proposed the perturbations of Pallas as a 

 prize-question. 



To these discoveries succeeded others of the 

 same kind. The German astronomers agreed to 

 examine the whole of the zone in which Ceres and 

 Pallas move ; in the hope of finding other planets, 

 fragments, as Olbers conceived they might possibly 

 be, of one original mass. In the course of this 

 research, Mr. Harding of Lilienthal, on the 1st of 

 September, 1804, found a new star, which he soon 

 was led to consider as a planet. Gauss and Burck- 

 hardt also calculated the elements of this orbit, and 

 the planet was named Juno. 



After this discovery, Olbers sought the sky for 

 additional fragments of his planet with extraor- 



