20 CELESTIAL MECHANICS: LEUSCHNER 



(3) JUNO 



Juno was discovered by Harding at Lilienthal near Bremen, Sep- 

 tember 1, 1804. Gauss computed several orbits successively correct- 

 ing the elements by new observations. Elements VII 1 corrected with 

 Bessel's observations, 1807. Ephemeris for 1808, April-December, 

 approximately given. (Elements A.) A number of additional orbits 

 were computed by Gauss' students at Gottingen (Wachter, Mobius, 

 etc.). 



Wachter 2 : Elements, (eccentricity omitted) from the last four 

 oppositions after Gauss' Method, (Neue Comment, der Gottingen K. 

 Societat, Bd. 1) including the opposition 1812. Eccentricity supplied 

 from Bode's Astronomische Jahrbuch, 1816, p. 233. (Elements B.) 



Mobius 3 : Oppositions used: 1810, 1811, 1812, 1813. Correcting 

 mean longitude by +4'55", the representation of the observations 

 1815, March, is +8" in longitude, and 51" in latitude. (Ele- 

 ments C.) 



Nicolai 4 at Seeberg, near Gotha, compared Gauss' observations 

 with the orbit of Mobius, (empirically correcting L) , determined the 

 oppositions and derived new elements. Oppositions used: 1811, 1812, 

 1813, 1815. "Juno is nearly in conjunction with Jupiter and the 

 perturbations may be large." (Elements D.) 



Taking up the determination of the large perturbations by Jupiter 

 by the method of special perturbations, Nicolai 5 derived a new set 

 of elements. Oppositions used: 1811, 1812, 1813, 1815, 1816, 1817, 

 1818. Representation of observations in 1819, Aa+2',6 AS 0'.2. 

 (Elements E.) 



Not satisfied with the representation of the observations by his 

 last set of elements, Nicolai 6 extended the computation and deter- 

 mined new elements, -which represented the observations of the 

 "Atom" well in 1820. Oppositions used: 1805-1819. Special per- 

 turbations by Jupiter. Representation of the observations 1820, May, 

 Aa 7", AS 2". (Elements F.) This computation of the special 

 perturbations was continued for some years. 



In 1823, Nicolai 7 derived his final set of elements, including the 

 determination of the Jupiter mass, for which he found 1/1053.924, in 

 agreement with the value Gauss had found from his theory of the 

 motion of Pallas. The representation of the observations cannot be 

 improved by taking Saturn or Mars into consideration, but Nicolai 

 considers the possibility of the active mass of Jupiter changing with 

 the body acted upon. From these elements osculating elements for 

 1826 were computed, taking account of the special perturbations by 



