Could a spacecraft orbiting Saturn, like Cassini, use a Titan gravity assist to leave the Saturn system (e.g. to bring a sample back to Earth), without using fuel other than to reach Titan?

  • $\begingroup$ How should a sample collected from an orbit around Saturn? $\endgroup$
    – Uwe
    Aug 29, 2017 at 17:57
  • 2
    $\begingroup$ @Uwe From the plumes of Enceladus (like Stardust). From flying through Titan's upper atmosphere (like Maven). By touching down on microgravity moons such as Pan (like Hayabusa). And maybe picking up a few ring particles. The Saturn system is a smorgasbord for sampling without landing or entering any gravity well. other than Saturn's. So I wonder if Titan could eject such samples, or say Cassini, back to Earth for free. $\endgroup$
    – LocalFluff
    Aug 29, 2017 at 18:54
  • $\begingroup$ Related: space.stackexchange.com/questions/22737/… $\endgroup$
    – Hobbes
    Aug 29, 2017 at 19:30
  • 2
    $\begingroup$ "Escape Saturn" and "Enter return trajectory to Earth" are two goals separated by a rather significant delta-V cost. $\endgroup$
    – SF.
    Aug 29, 2017 at 21:15

1 Answer 1


You'd need to get to Jupiter to get an assist to Earth. It might be possible. See Saturn Escape Options for Cassini Encore Missions and Cassini End-of-Life Escape Trajectories to the Outer Planets. You can certainly escape Saturn with multiple Titan flybys. Getting to Jupiter is trickier, and requires the right timing and a lot of patience. Low-energy Saturn-Jupiter transits are available about every 20 Earth years.

  • $\begingroup$ Why would one have to go via Jupiter back to Earth? Why not directly Saturn-Earth? $\endgroup$
    – LocalFluff
    Aug 29, 2017 at 21:38
  • $\begingroup$ You're just not going to be able to get that much change in velocity from Titan. $\endgroup$
    – Mark Adler
    Aug 30, 2017 at 0:17

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.