General relativity predicts that massive bodies, when they are accelerated, radiate gravitational waves , warping space-time as they propagate through the universe at light speed. Cassini's RS can and will search for such gravitational waves. The best time of year to do this when Cassini is at opposition , that is, on the same side of the Sun, in line with the Sun and Earth. That way, the Sun is out of the way, contributing minimum noise to this sensitive experiment. Then the spacecraft is commanded to be quiescent, so that nothing will interfere with Cassini's steady speed, like rocket thrusters firing.
Coherent tracking is established.
Other spacecraft have done this kind of experiment in the past, and have not detected gravitational waves. Earth-based gravitational wave detectors are also being invented. Cassini's use of Ka-band will provide a new level of precision to this exciting search. Even if no gravitational waves are detected, that fact in itself is useful, for determining constraints to apply within the theory. Other scientific experiments, such as imaging or spectroscopy, are mostly based on individual instruments aboard Cassini.