Ephemerides of the outer Jovian satellites

Abstract

The results of the determination of orbits for 54 outer satellites of Jupiter based on all available observations of these satellites are presented. The problem was solved using numerical integration method applied to the equations of satellite motion. After initial conditions of integration were refined, the residuals of observations from theory were obtained. Values of root-mean-square residuals for the eight satellites JVI-JXIII in right ascensions and declinations were found to be in the range 0.48 �� −0.67 �� . The same parameters for the new outer Jovian satellites are in the range 0.10 �� -0.46 �� . During the process of numerical integration of equations, the series based on the Chebychev polynomials for the satellite cordinates were defined. The series are used to calculate the apparent positions of satellites at the ephemerides. This ephemerides tool has broad capa- bilities including the possibility of obtaining residuals for a large series of user observations. The satellite motion model and numerical integration method adopted in this work were compared with the methods used at the Jet Propulsion Laboratory. This comparison of the apparent positions of satellites has shown that the differences between the two models are not greater than 0.012 �� in a 100-year interval. The residuals of satellite observations are similar to those obtained at JPL.