I worked for NASA at JPL for over 35 years. the most exciting projects were those that require a high degree of autonomy. Mars rovers were a special challenge because of the long round trip light time between Earth and Mars. If you had to rely on ground based control alone the vehicle would never be able to travel more than a few kilometers because every step would require a Q&A exchange between the vehicle and the controllers. A Titan submarine is this problem in spades. Not only is the round trip communications time an order of magnitude greater the sub is likely to be out of communications for extended periods of time because much of its mission will be submerged. This requires a very high level of on-board intelligence. A remarkable challenge but the folks designing these things are definitely up to the task.
Hydrocarbon as fuel would only work if it can be oxidized. I doubt there is any oxygen present, but perhaps oxygen should be the simple "fuel" to take as cargo.
The thing is, there are probably a lot of us that have now retired, that would be willing to take a one way journey to explore our solar system, or make it as far as our age and the amount of supplies they could pack around us would last. I know I would.
The hurdle qualifying to leave earth would probably disqualify me..and I'm not retired. I certainly would relish the opportunity to explore provided I have my kindle and a library of books to read to help pass the millions and millions of miles. :) Oh, and I want to be able to send images home to show my kids where dad is now.
A great idea from the pure science point of view, but I don't want government funding any more space activities unless they are defense related, as the moon shots really were.
I wish I had billions of dollars that are cunningly looted from millions of innocent victims to spend on what extravagant "greater good" whim I could come up with. Actually I don't, never have and never will.
What a wonder that will be. Can life exist in a methane atmosphere? It's stuff like this that makes me want to live forever. By the way, what's that white thing on the ship's tower? It looks like a duck.
Maybe its my sci-fi authors mind but why burn anything? I would think, and ,I haven't done any looking, that some type of chemical reaction using methane could result in electrical charge that could be used to provide power, much like salt water did for my personal submarine idea in Shadows Live Under Seashells.
If they can negate the corrosion and use the entire sea of methane as an element of the electricity making chemical reaction the sub "could" go on for many years. The trouble I see with burning is that should that make contact with its surroundings.....
Not sure that a spark or even a constant flare would matter in a sea of methane, as there is no free oxygen present. I am thinking that to have an internal combustion engine there, there would have to be some way to generate oxygen on the spot to keep the sub going.
With that in mind I withdraw my suggestion to burn methane.
The image is so cool. It instantly reminds me of Ben Bova's Jupiter. The protagonist is a young man, new to space, who goes in a submarine-like vehicle into Jupiter's atmosphere down past where it takes on the properties of a dense high-pressure liquid. He's not only an outsider among the crew working near Jupiter, but he's a Christian, and in this time some people lump all religious people, even total moderates, in with extremists.
Actually I don't, never have and never will.
With that in mind I withdraw my suggestion to burn methane.