Re: [Space]Steampunk Firefly Idea
 

Compared to Star Wars and Star Trek, maybe.

Re: [Space]Steampunk Firefly Idea
 

Apart from sentient machines I don't think Steampunk ever goes beyond what probable

Re: [Space]Steampunk Firefly Idea
 

Steampunk covers a lot of ground from fully realistic alternate history to the more fantastical and everything in between. Cyberpunk, for example, was never realistic.

I tend to think of slightly soft-ish Steampunk as the Murdoch Mysteries aka The Artful Detective show from Canada. Most of the anachronistic tech is at least technically possible.

Re: [Space]Steampunk Firefly Idea
 

TL7 space flight technology culminates in the Saturn 5. The Shuttle was designed at TL7 but didn't fly until tL8 and was continually modified at TL8. Neither of them (or anything real at TL7) would allow you to colonize even out Moon (and even if it had a breathable atmosphere).

Also for your early missions you need a VTOL launch and land that can alnd with a full fuel load or somehow make its' own fuel with a Spaceships Refinery module. That's not tL7 (or even 8) either.

This was why I recommended superscience. Steampunk tends to be full of the stuff starting with the power plant of captain Nemo's Nautilus.

Re: [Space]Steampunk Firefly Idea
 

I tend to think of Steampunk, in this context, to mean internal feel rather than truly Victorian level technology and culture.

Though even TL 7 is quite more advanced than the Victorian age. So why not go back a bit to TL 5/6 and add a hint of superscience?

Re: [Space]Steampunk Firefly Idea
 

Would a more conventional but reusable lift vehicle suit you better? (There's some interesting overlap between the complexities that requires and Steampunk) And I figure that the first wave of colonists would be dropped off in 30 Ton Drop Cans, not reusable spacecraft, they'd have the equipment to build a small spaceport for later use but.

Re: [Space]Steampunk Firefly Idea
 

Well, you only need 1 man and 1 woman to start a colony. Apollo sent 24 people to lunar orbit in a span of 4 years, for exploration and political gain, so this setting could maybe up that by an order of magnitude for colonisation purposes, multiplied by the number of countries involved in the space race.

And there's no reason a return flight has to be necessary, which makes it easier than Apollo was. Furthermore, as the moons have atmospheres, landing is just a matter of deploying parachutes, which saves on the delta-V needed. If refuelling is necessary, using local fuel sources might be sufficient depending on the tech. I'm guessing these habitable moons may have trees, crops, coal and oil available.

Another thing to consider is 3 moons around a gas giant is a different set of orbital mechanics than Earth-Moon. First is escaping your moon's gravity, but that puts you in the gas giant's orbit at a certain orbital speed. Transferring to the orbit of another moon is then a matter of gaining or losing orbital velocity, as well as transferring to its orbital plane. I tried to look at moving from Io to Europa as a comparison, but the outer moon has a slower orbital speed so I'm not sure what that means. The difference is about 3 km/s though, compared to Apollo's delta-V budget of 16 km/s, so my feeling is that it's easier in this setting to get around than looking at what the Saturn V could do. Transfers might also be assisted with slingshots from intermediate moons, making interlunar travel even more efficient. A concerted colonisation drive might also set up a low-orbit slingshot tether launcher, similar to what Stephenson describes in Seveneves.

So, I don't see big problems with colonisation in this setting at TL 7 or so, especially with a few dabs of steampunk superscience.

Re: [Space]Steampunk Firefly Idea
 

Multiple moons offer the possibility of using very low energy transfer orbits to get around -- on the order of hundreds of meters per second delta-V, rather than multiple kilometers per second. See, e.g., Ross and Scheeres 2007.

Re: [Space]Steampunk Firefly Idea
 

Indeed, and I'm sure most NASA probe missions are done on a fairly low delta-V budget.

Another option if the gas giant has a significant magnetic field is electromagnetic tether propulsion or magnetic sails. These things sound high tech to us, but in this setting, whose science grew up in this environment, they would be a plausible advanced tech path. It could even be more steampunk, with spacecraft running Edison-style electric generators powering massive steel web magsails, navigated by captains who have gained an instinctive feel for the magnetic field patterns around the primary and its moons. These magships may not even be able to land, requiring shuttles, launch catapults and skyhooks to handle the surface-orbit stage.

ETA: I was just reading about the Io Plasma Torus. Could something like this be used like trade winds, giving a free velocity boost to magsail ships?

Re: [Space] Steampunk Firefly Idea
 

Ooh, that's a nifty idea. The combination of magsails and low-impulse trajectories gives a great feel.

If the moons are habitable, they probably require fairly significant magnetic fields of their own to shield from particles streaming off the gas giant. A sufficiently strong magnetic field and correspondingly excellent magsails would allow launch from the moons' surfaces, although only at their magnetic poles -- which also receive the concentrated particle flux, making them quite unhealthy. Magnetic shuttles, run by convicts and highly-paid short term volunteers?