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I'll shamelessly resurface a comment I made a few years back. There's a school of thought which views Venus as a better colonization candidate than Mars, and a

I'll shamelessly resurface a comment I made a few years back. There's a school of thought which views Venus as a better colonization candidate than Mars, and as early as the 70's scientists envisioned floating cities. From https://en.wikipedia.org/wiki/Colonization_of_Venus https://en.wikipedia.org/wiki/Colonization_of_Venus: In effect, a balloon full of human-breathable air would sustain itself and extra weight (such as a colony) in midair. At an altitude of 50 kilometres (31 mi) above the Venusian surface, the environment is the most Earth-like in the Solar System beyond Earth itself – a pressure of approximately 1 atm or 1000 hPa and temperatures in the 0 to 50 °C (273 to 323 K; 32 to 122 °F) range. Protection against cosmic radiation would be provided by the atmosphere above, with shielding mass equivalent to Earth's. Being able to wear a simple breathing mask while working outside instead of a full pressure suit is a boon. Of course high windspeeds and the constant bombardment of acid rain would be a problem. I could imagine Venus one day being an exotic, cloud-top paradise for the rich (reminiscent of BioShock Infinity) that's expensive to maintain, and Mars a brute workhorse that eventually displaces it as a more resilient habitat over the very long term (eg. after terraforming).

usrnm 6mo ago
Zeppelins on Venus are the perfect mix of scifi and steampunk, I would really wish to see that one day
Balgair 6mo ago
Likely the Moon or Mars will be where we do a lot of bulk commodities, since the Delta-V to get the goods off of them will be lower. Then you'll have raw resource extraction in the asteroids and other very light moons. Earth will remain as the furnished goods and services location due to labor availability. A classic triangle trade ala the sugar, rum, and slave markets in the North Atlantic in the 17-1800s. https://en.wikipedia.org/wiki/Triangular_trade https://en.wikipedia.org/wiki/Triangular_trade
- sidewndr46 6mo ago
  The way you capitalized the 'V' in Delta-V had me thinking that somehow the Delta rocket family was back for a fifth iteration
- pstuart 6mo ago
  I'd think the moon would be the best primary target due to proximity and the ability to possibly use large rail guns to get finished goods up into orbit.
credit_guy 6mo ago
The problem with that school of thought is that nobody explains how you get from the balloons to orbit. The low Venus orbit velocity is about 7.3 km/s (similar to the LEO velocity), you need Falcon-size rockets to go from 0 to 7.3 km/s with enough cargo capacity to carry astronauts. Are you going to assemble such a rocket in a balloon?
- lmm 6mo ago
  > Are you going to assemble such a rocket in a balloon? Yes, or hanging off the side of it. What's the concern? If you want to launch a rocket from Mars you have to build it either inside your habitat (and then build an airlock big enough to fit a rocket through to take it out) or just outside it (which means working in vacuum the whole time), and I'm not sure being able to build a smaller rocket makes up for that.
  - credit_guy 6mo ago
    That's not how people intend to colonize Mars. Nobody is thinking of building rockets on Mars for a very long time. A few decades, maybe a century or more. The idea is to only refuel the rocket on Mars. You land the rocket (which comes from Earth) using aerobraking and retroburns. You refuel there. You take off. The only thing that gets manufactured on Mars is the fuel (technically the propellant). On Venus, you need to find a way to not land the rocket, but to make it stop gently next to the balloon, attach it to the balloon somehow, adjust the buoyancy of the balloon when this happens, so the balloon does not suddenly drop by 20 km where the pressure difference, and additional heat, can destroy it. Then you need to manufacture the propellant inside the balloon, then you need to find a way to make the rocket fire its engines and take off, but without destroying the balloon in the process, and you need to adjust the buoyancy of the balloon in reverse. Of all the steps, I'll grant that the manufacturing of fuel might be roughly as easy as on Mars (the Sabatier process and all that). But the rest have no parallel on Mars, and don't seem possible, no matter what technology we come up with.
    - lmm 6mo ago
      Landing/recovering aircraft on an airship is proven technology, and hooking a tether onto something as it falls through a buoyant atmosphere is quite possibly easier than stopping a rocket precisely at ground level where any screwup will turn it into a crater immediately (as is the case for Mars). Yes the balloon needs to be able to adjust its buoyancy to maintain stability but that was always a requirement; sinking into the atmosphere is a relatively slow process as long as your balloon is big enough. Likewise air-launched rockets are already proven technology - you can either just let the rocket drop away far enough for clearance before lighting its engines, or if you're feeling fancy then the rocket uses its own sacrificial balloon to rise as high as possible in the atmosphere before launch (of course that means you have to be able to manufacture balloon fabric or arriving rockets have to bring their own until you reach that stage, but that doesn't seem insurmountable).

usrnm 6mo ago

Zeppelins on Venus are the perfect mix of scifi and steampunk, I would really wish to see that one day

Balgair 6mo ago

Likely the Moon or Mars will be where we do a lot of bulk commodities, since the Delta-V to get the goods off of them will be lower. Then you'll have raw resource extraction in the asteroids and other very light moons. Earth will remain as the furnished goods and services location due to labor availability. A classic triangle trade ala the sugar, rum, and slave markets in the North Atlantic in the 17-1800s. https://en.wikipedia.org/wiki/Triangular_trade https://en.wikipedia.org/wiki/Triangular_trade

sidewndr46 6mo ago
The way you capitalized the 'V' in Delta-V had me thinking that somehow the Delta rocket family was back for a fifth iteration
pstuart 6mo ago
I'd think the moon would be the best primary target due to proximity and the ability to possibly use large rail guns to get finished goods up into orbit.

credit_guy 6mo ago

The problem with that school of thought is that nobody explains how you get from the balloons to orbit. The low Venus orbit velocity is about 7.3 km/s (similar to the LEO velocity), you need Falcon-size rockets to go from 0 to 7.3 km/s with enough cargo capacity to carry astronauts. Are you going to assemble such a rocket in a balloon?

lmm 6mo ago
> Are you going to assemble such a rocket in a balloon? Yes, or hanging off the side of it. What's the concern? If you want to launch a rocket from Mars you have to build it either inside your habitat (and then build an airlock big enough to fit a rocket through to take it out) or just outside it (which means working in vacuum the whole time), and I'm not sure being able to build a smaller rocket makes up for that.
- credit_guy 6mo ago
  That's not how people intend to colonize Mars. Nobody is thinking of building rockets on Mars for a very long time. A few decades, maybe a century or more. The idea is to only refuel the rocket on Mars. You land the rocket (which comes from Earth) using aerobraking and retroburns. You refuel there. You take off. The only thing that gets manufactured on Mars is the fuel (technically the propellant). On Venus, you need to find a way to not land the rocket, but to make it stop gently next to the balloon, attach it to the balloon somehow, adjust the buoyancy of the balloon when this happens, so the balloon does not suddenly drop by 20 km where the pressure difference, and additional heat, can destroy it. Then you need to manufacture the propellant inside the balloon, then you need to find a way to make the rocket fire its engines and take off, but without destroying the balloon in the process, and you need to adjust the buoyancy of the balloon in reverse. Of all the steps, I'll grant that the manufacturing of fuel might be roughly as easy as on Mars (the Sabatier process and all that). But the rest have no parallel on Mars, and don't seem possible, no matter what technology we come up with.
  - lmm 6mo ago
    Landing/recovering aircraft on an airship is proven technology, and hooking a tether onto something as it falls through a buoyant atmosphere is quite possibly easier than stopping a rocket precisely at ground level where any screwup will turn it into a crater immediately (as is the case for Mars). Yes the balloon needs to be able to adjust its buoyancy to maintain stability but that was always a requirement; sinking into the atmosphere is a relatively slow process as long as your balloon is big enough. Likewise air-launched rockets are already proven technology - you can either just let the rocket drop away far enough for clearance before lighting its engines, or if you're feeling fancy then the rocket uses its own sacrificial balloon to rise as high as possible in the atmosphere before launch (of course that means you have to be able to manufacture balloon fabric or arriving rockets have to bring their own until you reach that stage, but that doesn't seem insurmountable).