ORBITAL EVOLUTION OF JUPITER 8TH SATELLITE

The orbital evolution of Pasiphae, the 8th satellite of Jupiter, has b een investigated. Its osculating orbit for the epoch 29 October 1938 w as numerically integrated over the interval of 20,000 years. Within th e investigated time interval also the question of the Hill's stability has been studied. The Jacobian constant, generalized to the averaged elliptic problem, calculated from positions and velocities obtained by numerical integration, changes less than the order of 10(-8). The dom inant perturbations by the Sun to the satellite allow us to use the in termediate orbit of the averaged elliptic three-body problem for inves tigation of the evolutionary changes in the motion of the satellite. T he mean motion of the argument of perijove and the ascending node of t he satellite are defined by analytical formulae, using the osculating non-Keplerian ellipse with moving node and perijove, and changing ecce ntricity. The results obtained according to this theory are comparable with those calculated from the numerical integration.