  The JUICE mission will perform detailed measurements of the properties of the
Galilean moons, with a nominal in-system science-mission duration of about 3.5
years. Using both the radio tracking data, and (Earth- and JUICE-based) optical
astrometry, the dynamics of the Galilean moons will be measured to
unprecedented accuracy. This will provide crucial input to the determination of
the ephemerides and physical properties of the system, most notably the
dissipation in Io and Jupiter.
  The data from Planetary Radio Interferometry and Doppler Experiment (PRIDE)
will provide the lateral position of the spacecraft in the ICRF. In this
article, we analyze the relative quantitative influence of the JUICE-PRIDE
observables to the determination of the ephemerides of the Jovian system and
the associated physical parameters.
  We perform a covariance analysis for a broad range of mission and system
characteristics. We analyze the influence of VLBI data quality, observation
planning, as well as the influence of JUICE orbit determination quality. This
provides key input for the further development of the PRIDE observational
planning and ground segment development.
  Our analysis indicates that the VLBI data are especially important for
constraining the dynamics of Ganymede and Callisto perpendicular to their
orbital planes. Also, the use of the VLBI data makes the uncertainty in the
ephemerides less dependent on the error in the orbit determination of the JUICE
spacecraft itself. Furthermore, we find that optical astrometry data of
especially Io using the JANUS instrument will be crucial for stabilizing the
solution of the normal equations. Knowledge of the dissipation in the Jupiter
system cannot be improved using satellite dynamics obtained from JUICE data
alone, the uncertainty in Io's dissipation obtained from our simulations is
similar to the present level of uncertainty.
