Kaos

Nothing else than electricity is an unclear definition. If it would use the earth magnetic field to push against it, is it purely electrical? It would say no, as you use the earth then, which is nonelectrical to some degree. I guess the question is more about a completely refillable ressource in free space in our solar system. Then the mentioned approach of Escape Dynamics would qualify, as hydrogen is part of the solar wind and can collected, in principal at least.

In the beginning, construction of stuff on Mars would be more important, as a base there would be quite dependent on imports from earth. The sooner most of the things needed are constructed on Mars the cheaper the construction of a Mars colony would be. Beyond that point: A lot of money is made by selling some kind of data. Be it films, computer programs or scientific results. I mean: Would you have refused to buy KSP, if it was developed by some company on Mars? But there are also opportunities for selling material stuff: Delta-v from Mars to GEO is 7 km/s, delta-v from earth to GTO is 12 km/s. So transporting satellites, fuel or other stuff to GEO could earn them some bucks. This topic has to be seen a bit from the financial point of few: The construction is expensive and has to be supported somehow from earth. Be it gouvernancial, rich people that want to see a Mars colony or some other source. As soon as the colony is big anough and can produce most of its own stuff, the need some internal economy system (I know there is disagreement how big such a colony has to be or whether this is possible at all, but if it is not possible there will be no colony in the long run and I try to answer what a colony could sell. I also would discuss whether it is possible, but not in this thread). For the daily live, people on Mars would use some Mars currency for which they buy stuff produced on Mars. Nevertheless there would be some exchange between Mars and Earth currency, be it because some people find it cool to own 25 Mars bucks or some people want to trade something and need the other currency. If people on Mars can build rockets and deliver stuff to Earth, they can earn Earth money, even if they sell stuff that can be produced easily on Earth. Then Earth bound production would be a lot less complicated for the same goods an more profitable. But if the marslings strongly desire Earth money for some Earth goods, they would do it nevertheless. So something will be exported on the long run from Mars to Earth. But then of course it would be something where they get the most money per effort. This is why I suspect the main export goods to be data and stuff for other locations in the solar system.

You get plenty of solar power at the moon and there are various designs for how to store energy on the moon that are less effort than an RTG. Hence, even the long nicghts are not that problematic. So I would not use an RTG for a moon base, or only as backup.

My most unusual case of killing a Kerbal was a kraken attack: I just walked around with a single Kerbal in KSC, then he exploded.

With that little gravity on some of the moons, it might not be that difficult to come from one moon to another. So you do not need to find all the resources on one moon. Then it does not matter where you build the colony, you just gather the resources where they are and build the colony anywhere.

Artificial gravity by rotation is also possible on bodies which already have some gravity. So a low gravity is not that bad, as you might think. It requires more complicated buildings, that is right. But it is not impossible to live there.

I would like to skip the last name at all or to have different last names. A compromise might be to have last names, that are similar to Kerman, e.g. Keman, Ker, Cernan, ... But it is not that important in my opinion.

On many space related topics I am for far fetched plans, but colonizing the outer moons of the solar system should not happen before we have managed to construct at least one more or less self-sustaining colony on Mars, Moon, Venus or a near Earth asteroid, in my opinion. The outer moons combine a set of disadvantages against these closer targets: Much less solar power, more complicated to reach, more complicated to come back, longer communication delay to earth, we know less about them. Given a time where we already have several colonies at the closer celestial bodies, we should study them much closer to get more knowledge about them, before we make that a far-reaching decision, it will need a lot of effort, we should choose wisely. So at the moment, all of the decisions are equivalently taken without deep knowledge, so I choose Europa, because it has at least water and because of the film Europa Report.

I think diamond might go. We do not know how to make artificial diamonds of that size, but in principle it should be possible.

Carbon is ultra versatile. So I would guess it is possible (but for the fuel; RP1 is not only carbon, also you need an oxidizer, which might also not be carbon).

That is what I meant with "and one back"

Skylon should build an ion upper stage. Takes two years to GEO and one back, but Xenon does not tend to explode ;-p

Than you have misunderstood my plans, which means that I have not explained them good enough. Clearly I have not explained every part that I have in mind. There is a ever growing cloud base. You go there from earth again and again, but you do not return there directly form orbit of Venus. The base consists of docked modules. Some of these are brought from earth, some are constructed from resources from Venus. If you want to go to this base, bring something with you that can stay on its own in the clouds. Then you have a lots of time for docking. But as soon you have docked to the base, you can use it, expand it or life there. When the base is big enough, that you can build a bigger landing platform in there. At that point you can land and do not need to bring the capability to stay in the clouds with you. But this addition is for later. Then there is a Venus orbital base. The main purpose is to dock vehicles that have returned from the cloud base. From there you can fly back to earth, be it crew or surface samples. The orbital base is supplied from earth. Only in the long run it is supported from Venus, be it that you managed to construct rockets on Venus, have fully reusable launch vehicles, or both. Only if this point is reached, a return from the orbital base to the cloud base is used.

I have seen a reusable upper stage planing in a Skylon video: It is brought with Skylon to orbit. Then it transfers the payload to GTO. It then returns to LEO without the payload and returns with the next Skylon available to earth. As with most of the Skylon plans for me: I am not sure that it works, is economical or is technical feasible. But it sounds cool. This plan again is no SSTO anymore. But it shows a bit why SSTO are not used: Even if there is a comparable cheap way to go a good part of the way to orbit, not carrying so much mass around is better, so no SSTO design is used -- even on the proposed SSTO designs not for all operation modes.

My current plan includes (at least in the early stage, where you do not build rockets on Venus, what you should do at some later point) Robots from Earth to Venus clouds, brake with parachutes & balloons, stay there Manned from Earth to Venus clouds, bring empty return rocket with you, brake with parachutes & balloons, dock with robotic stations with resources Manned from Earth to Venus clouds, bring empty return rocket with you, land on some flying landing plattform Manned from Venus clouds to Venus orbit with the rocket Venus orbit supplied an crew rotation from earth You see, there is no return to Venus clouds in it.

LEO is more like 7 km/s. You need 9-10 km/s to come there with a typical rocket, that is right. But you loose a lot due to gravity and air resistance. But when you have 2 km/s in this height, you already had most of this losses.

Where are these 343 m/s from? http://www.reactionengines.co.uk/space_skylon_tech.html states Mach 5.5, which is closer to 2 km/s. Which is still a lot till orbital velocity, but not neglectable.

Whom are you referring to? And what do you mean by BACK? From Earth to Venus? From surface to clouds? From Venus orbit to Venus clouds?

Rising to 10 km also in case of overheating is a good comment. Sounds plausible that helium diffuses faster. I just know of the problem with brittleness by diffusion with hydrogen. Another thing I made a mistake in recalling memory here, was that I know that it is a problem to store high pressured hydrogen because of diffusion. But as we have 1 bar here, I do not really know, how big the problem is. Multiple vehicles have to problem that they require more docking. Docking balloons is much simpler than docking planes or docking in space, but still something that can cost time. But I see the advantages: The mining hardware does not have to be lifted all the way up, the lifting hardware for the higher part does not have to be that much heatproof.

I kind of proposed that already in the thread. Just with realistic technology. And as this thing is huge, it needs too long to be mined to dust, so instead I just use the push of it.

These rockets are huge! 6 m/s looks slow with these things.

What is used is not a question of efficiency in terms of mass-to-LEO, but what is cheap and economic.

I mainly though about asteroids from the asteroid belt. You are right, this argument does not count for some of the closer asteroids. The other arguments still count.

Lets talk about the lifting gas: Breathing air: only half the buoyancy than helium, but you can walk in it. I think this advantage should not be ignored, as it is very important for human to be able to walk around. There is not much free space there. Helium: As said: Double the buoyancy, but much more complicated to get. So you might be able to construct more than twice as big structures if you use breathing air instead. Hydrogen: Easier to get than helium, nearly the same buoyancy. But due to its small molecules it diffuses through other stuff which results in a loss of hydrogen over time and makes surrounding material brittle over long time. So you should not use it besides short missions. If you have oxygen close to it, even if separated by a wall, it is even worse, not least due to diffusion, but the brittleness-problem is bad enough. So I would use breathing air as lifting gas for most purposes.

Ok, I was a bit off-topic. Nevertheless, I think some kind of ground activity is needed for a big cloud base.