C 115 ] 



XIX. Ohservntions a?id ]\Teasurcmpnts nf llw Vianet Vesla. 

 By John Jbuome Schkoetek, 1\ R. S. Translated 

 from the German *. 



XXT our verv first observations with nia2;nifying powers of 

 150 and 300, applied to the excellent new ]5-ft'et reflector, 

 we found the planet Vesta witliout any appearance of a disc, 

 merely as a point like a fixed star, with an intense, radiating 

 light, and exactly of the same appearance as that of any 

 fixed star of the sixth magnitude. In the same rnanner we 

 both afterwards saw this planet several times with our naked 

 eyes, when the sky was clear, and when it was surrounded 

 by smaller invisible stars, which precluded all possibility of 

 mistaking it for another. This proves how very like the in- 

 tense light of this planet is to that of a fixed star. 



As the observations and measurements of Ceres, Pallas, 

 and Juno, were made with the same eye-glasses, but with 

 the 13- feet reflector, we soon after compared the planet 

 Vesta with the same glasses of ISfi and 288 times magnify- 

 ing power in the 13-fcet reflector. In both these telescopes 

 its image was, without the least difference, that of a fixed 

 star of the sixth magnitude, with an intense radiating light; 

 so that this new planet may with the greatest propriety be 

 called an asteroid. 



April 2Cth in the evening, at nine o'clock, true time, I 

 succeeded in effecting tlie measurement of Vesta, with the 

 same power of 288, by means of the 13-feet rehcctor, with 

 which that of Ceres, Pallas, and Juno, had been made; and 

 when viewed by this reflector it also appeared exactly in the 

 same manner. Of several illuniinatcd discs, of 20 to 0-5 

 decimal lines, which I had before made use of for measuring 

 the satellites of Saturn and Jupiter, the smallest disc only (jf 

 0*5 lines coidd be used for this purpose ; by it the rounded 

 nucleus of the planet Vesta, when the disc was at the di- 

 stance of Giro lines from the eye, appeared at most of the 

 same size, and I must even estimate its diameter as onc- 

 sixlh smaller. If, therefore, we attend not to the full mag- 



' From Tru>isailioii% of thr lioi/al Sucirli/. purt ii. for lti07. 



11 2 nitude 



