Is it feasible to retrieve ice from Saturn's rings or methane from Titan?

[DanClemmensen]

In golden-age science fiction, ice was obtained from Saturn's rings, and asteroid mining was assumed also. Methane from Titan is slightly more recent.

Is any of this actually practical? It's clearly qualitatively feasible, but will it ever make economic sense?  For the ice, the idea is to use some sort of high-efficiency, low-thrust propulsion to move huge payloads from the rings to LEO or other destinations, taking years in transit. The propulsion units would return to the Saturn system in an endless boring cycle.

For methane from Titan, you first need to move it from the surface into Titan orbit, and then handle it like the ring ice. for the surface launch, a methalox booster makes sense if you are already mining ice in the rings.

[nicp]

Ah, The Martian Way, Asimov. At least ice retrieval from Saturns rings.
I doubt it would it’s practical to return ice to the inner Solar System due to deltav requirement. Use locally, sure.
Methane from Titan, or gas from any atmosphere has been discussed on this site and I think the consensus is negative but I would have to search for those discussions.
EDIT: I missed your reference to the surface of Titan. That is surely not an absolute requirement.

[DanClemmensen]

Ah, The Martian Way, Asimov. At least ice retrieval from Saturns rings.
I doubt it would it’s practical to return ice to the inner Solar System due to deltav requirement. Use locally, sure.
Methane from Titan, or gas from any atmosphere has been discussed on this site and I think the consensus is negative but I would have to search for those discussions.
EDIT: I missed your reference to the surface of Titan. That is surely not an absolute requirement.

Yep, it's all about Δv. It won't work at all unless you have exceptionally low cost thrust. However, since there is no time constraint, you can apply that thrust continuously and at low power.

[nicp]

As an easily (for some value of easy) available reaction mass, Saturn’s rings appear to be a good bet. Asimov was imaginative.
I suppose some comets could do the same?

[ccdengr]

At one point it was thought that methane was a major component of Titan's atmosphere, so you have the scooping operations described in, e.g., Arthur C. Clarke's IMPERIAL EARTH.  But in reality there's only about 1 percent methane, at least in the upper atmosphere, so it's harder to get (you'd have to scoop it out of the lakes or at least dive well down into the troposphere.)

[DanClemmensen]

At one point it was thought that methane was a major component of Titan's atmosphere, so you have the scooping operations described in, e.g., Arthur C. Clarke's IMPERIAL EARTH.  But in reality there's only about 1 percent methane, at least in the upper atmosphere, so it's harder to get (you'd have to scoop it out of the lakes or at least dive well down into the troposphere.)

Titan has hydrocarbon lakes or seas, and I assumed that liquid methane is available on the surface of these. My thought(?) would be to build a floating processing facility that can also launch and land the local tankers. These tankers just get the methane to the (huge) transporter in Saturn orbit. These transporters then take years to take the methane to LEO.

This assumes the goal is methane in LEO for rocket fuel. If you want it for the carbon, you can send higher hydrocarbons from those same surface lakes or seas.

[ccdengr]

There's lots of ice on Ceres and probably Vesta, no need to go all the way to Saturn for it.

[DanClemmensen]

There's lots of ice on Ceres and probably Vesta, no need to go all the way to Saturn for it.

Ceres is roughly half ice, and has a volume of 434,000,000 km³. That's a lot of water.  It's still lot of Δv, but a lot less than from Titan or Saturn's rings.
   https://en.wikipedia.org/wiki/Ceres_(dwarf_planet)

[Skye]

Yes, it absolutely is. Just not yet. Wonder how they’ll do it