  Launch of the Gaia space observatory started a new era in astrometry when the
accuracy of star coordinates increased by thousands of times. Significant
improvement of accuracy was also expected for the coordinates of the Solar
system bodies. Gaia DR3 provided us with the data which could be used to test
our expectations. In this work, we refine the orbits of a number of outer
planetary satellites using both ground-based and Gaia observations. From
thirteen outer satellites observed by Gaia, we chose six to obtain their
orbits. Some specific moments in using observations of outer satellites made by
Gaia are demonstrated. These pecularities stem from scanning motion of Gaia, in
particular from the fact that the accuracy of observations is significantly
different along and across the scanning direction. As expected, Gaia
observations proved to be more precise than those made from Earth, which
results in more accurate satellite ephemerides. We estimate accuracy of the
ephemerides of considered satellites for the interval between 1996 and 2030. As
astrometric positions published in Gaia DR3 were not corrected for the
relativistic light deflection by the Sun, we took into account this effect,
which slightly diminished the rms residuals. In addition, relativistic light
deflection by the giant planets was estimated, which, as it turned out, can be
neglected with the given accuracy of Gaia observations.
