The space elevator idea would require too much initial investment, something like the entire GDP of the US for multiple years.. and even then there is no guarantee we can solve the technical hurdle of the tether itself.. The idea is good, i suspect if someone does attempt it, it will be much less ambitious. Maybe a buckfuller sphere (if its large enough it is lighter than air) tethered to the stratosphere capable of ferrying heavy payloads 10 miles up then it launches from there..Active positioning would keep it in geo-synchronized.. Probably cut the price per pound significantly .

-ddn

The space elevator idea would require too much initial investment, something like the entire GDP of the US for multiple years.. and even then there is no guarantee we can solve the technical hurdle of the tether itself.. The idea is good, i suspect if someone does attempt it, it will be much less ambitious. Maybe a buckfuller sphere (if its large enough it is lighter than air) tethered to the stratosphere capable of ferrying heavy payloads 10 miles up then it launches from there..Active positioning would keep it in geo-synchronized.. Probably cut the price per pound significantly .

-ddn

This sounds a lot more likely to me than building a full-fledged space elevator or blasting to the moon robots capable of building an on-site base and factory remotely. Thing is, we can already go to space pretty reliably. It's just a question of what we're going to do there that really stops us from going a lot. I remember reading that even if the lowest orbital level above the earth were filled with solid gold, it still wouldn't be worth the cost of going to get it.

Cutting the cost of going would certainly foster going more often (a la the full space elevator concept), but that still doesn't make being in space any more valuable (in terms of a return on the reduced cost of going + the distributed cost of the elevator).

Increased energy production would be great, and certainly be more plausible than things like manufacturing or colonization (at present, at least). But we will have not only the above-mentioned issues regarding actually getting the energy back to Earth in a usable form, but also have to contend with the fact that we can produce enough energy to use, even factoring in expanding populations and the increased consumption that they'll bring, fairly cheaply with regard to up-front investment.

Getting to that energy, whether it's oil or natural gas, as well as using it increasingly ravages the planet as we use up the easy sources, but those costs tend to be externalities to the producers and gradual enough not to be noticed by the consumers most affected by those externalities.

So we end up with people pushing for more energy now, as cheaply as possible, which leads to the lowest possible short term costs and no thought to the long term costs. This is a tradeoff that humans (and all of class mammalia really) tend to choose, even when it is not rational as compared with longer term/greater reward options.

We just need "someone" being there taking the initiative. A "google" style kind of paradigma, wealthy enough to set the bases for a prosperous business. I forsee (as many others) that getting to build anything on the moon and throwing it back to earth, at some point could be cheaper than building it overseas and shipping it. But as long as we don't go there and start digging we will never know.

I can imagine a sort communication satellite factory there. I'd be even willing to accept the US/Russia placing some nukes there as a defense system if only just to get us out of here for once. We really need to get out of here before an asteroid hit or over population eat us.

We just need "someone" being there taking the initiative. A "google" style kind of paradigma, wealthy enough to set the bases for a prosperous business. I forsee (as many others) that getting to build anything on the moon and throwing it back to earth, at some point could be cheaper than building it overseas and shipping it. But as long as we don't go there and start digging we will never know.

I can imagine a sort communication satellite factory there. I'd be even willing to accept the US/Russia placing some nukes there as a defense system if only just to get us out of here for once. We really need to get out of here before an asteroid hit or over population eat us.

The issue is that "someone" is likely to end up being a sucker. The reason that there isn't a flood of investment for this sort of thing already is that no one forsees a return on laying the infrastructure. It's sort of like the big rail speculation in Europe during the Industrial Revolution or the laying of fiber optic cable by big telecom companies more recently.

The speculators did in fact forsee value in their activities, and they were right-- lots of freight lines and lots of data transmission capacity were certianly useful and provided a backbone for later investors to utilize that capacity in innovative and valuable ways. But the major investment in capacity before there were really applications to use that capacity left a lot of those speculators holding the bag, because it took a while for the capacity to actually be utilized.

I don't think that current investors have really learned from the past as far as this is concerned (there are still investment bubbles pretty much all the time), but more that the time horizon for getting returns on space investment is long enough to not be attractive to them. I'll agree that we can come up with ways to get value, even a lot of it, from being on the moon or otherwise in space. It's just not close enough to get much private investment flowing.

That leaves government investment to make it happen. This, however, faces the same risks as private investment and even to a greater degree (there will always be some politician or activist group to decry the investment that isn't paying off yet, and won't for some time). In the face of some decidedly non-economic concerns, like the space race of the 1960's, even that can be overcome. But the world isn't currently concerned with finding ways to channel prosperity which capture the human imagination.

I would rather see a big push in research to potential values in going to space or the moon, which can then be used to make doing so more attractive. Research is valuable on its own, and more likely to lead to developing things like moon bases (perhaps even at lower upfront cost) than embarking on a global feat of engineering first and trying to make it useful later on.

I don't think it's strictly necessary to build a space elevator. You can build mass to orbit on the open market - I think it's about $3000 a pound (kilo? I can't remember) on Proton, and SpaceX is pitching that they can do $1,000 a pound on the Falcon 9 Heavy if they can find customers for a minimum of four rockets a year.


Their system is "evolvable" to being reusable, provided that the numbers work. In other words, if you build enough payloads, than they can revise it to further reduce the cost. So it is a system designed to be cheap on a low number of flights, but scale up fantastically.

From there, there are about a thousand ideas for cheap space access, including space elevators, that you could probably find investment for if there was a business case, and you'd close that case by building payloads.

The Shuttle tried this several decades ago by aiming for $200 a pound on the assumption that they would be performing about fifty launches per year, however this failed for a number of reasons, including the fact that by design it requires a crew and after Challenger they decided to avoid superfluous use of it, restricting its flight rate to a low figure.

The problem of space flight is, in short, a matter of manufacturing economics. Complex systems like the space shuttle, scramjet reusables, virtual SSTOs, space elevators, have substantial R&D costs, manpower and talent needs and this translates to cost of existence. The Shuttle, for example, cannot exist as a usable system without a few billion dollars a year. This means that complex systems can be cheap if you have enough to loft.

How is this relevant? There are efforts by space advocates to make up business cases and plans to utilize space in order to boost flight rates.

Space tourism is one of these. There's interest in this sector and attempts to offload cost of existence onto "space tourists" because various studies show you could fill several dozen seats a year. The rich people paying to be flogged into space basically serve as seat fillers to subsidize the existence of space access and make probes and other work cheaper.

Space based power is another. Whether it really makes sense, I don't know, but if you had a mega project to build damn near anything of this scale in space, you would need to buy many dozen launches per year, which would push down the costs of space access dramatically.

So current launch cost estimates are not totally relevant, at least not in a consuming way. The mere existence of such a program would probably push down the costs of current launch services including Proton, Falcon, Atlas, etc. etc. and if it looked like a safe bet that it'd continue long term, there would be private sector investment to create more advanced systems.

This can feed into a cycle if lowered launch costs boost tourist flights (studies suggest they would) and alter the economics of other ideas, making other businesses viable, further boosting flight rates.

They do not and should not concern themselves with space elevators. Simply by existing and making sense on any level, such a system could knock space access costs flat and make it possible for public sector organizations like NASA to afford Mars settlement.

So we come back to that first question. Does it make any sense at all?

These sorts of schemes show up all the time. ALL THE TIME. I wouldn't spend a second worrying about whether or not Japan is actually going to do this.

But I feel I ought to clarify that the purpose of space based power is in part to get around the atmosphere by capturing sunlight that is hampered by atmosphere and converting it into wavelengths such as RF that are not.

That's the magic.

There's also the fact that the Moon nor any other sat not in GEO doesn't have direct line of sight with any particular country on the ground, so if you were to build one, you can also sell power to other people under the sat's ground path (i.e. anyone who can see the Moon, ever).

Beyond that, I don't know.

I do find it a little interesting that we think we can manufacture out way out of energy scarcity.

If we can do that, does it really even matter how it compares to oil? Fossil fuels are pretty much always going to win near term cost figures because they're basically a freebie; they're accumulated solar power from millions of years, waiting to be sucked out of the ground. They're useful in that they let us industrialize and develop the advanced technology that lets us move on to the next thing without going back to pre-industrial misery.

How much did we just spend on war in Iraq and other bullshit in the middle east?

Are there a dozen ways we could have manufactured out way out of energy scarcity with that?

Couldn't we basically try all of them for that sum? Thorium reactors, photo voltaics, on every roof, build all the new power infrastructure we need for renewables, etc. etc. etc.

Now, when fossil fuels are economic winners, is the time to do this, because if we're hitting peak oil or peak whatever and prices are growing and everything is going to shit is probably the worst time to raise money to build a ring around the Moon.

I would rather see a big push in research to potential values in going to space or the moon, which can then be used to make doing so more attractive. Research is valuable on its own, and more likely to lead to developing things like moon bases (perhaps even at lower upfront cost) than embarking on a global feat of engineering first and trying to make it useful later on.

I totally agree. Scientists are discovering "new elements" already and predict we could be close to get to the "Island of Stability". Who knows what kind of new materials can be pulled from there!

Space elevators are a very important field of research for space exploration simply because of their potential ecological impact. That is, they can potentially be a 'green' system for the planet.

By building part of the counter-weight as a solar array, constructed from materials from the moon, it means you have near zero impact on the earth itself.



Of course, the other side of the coin is 'green rockets', basically exhausting materials that are harmless or beneficial to the weather cycle.

Power generation is not really a problem.

The big missing link right now is storage and transportation. Electricity at global scale simply cannot be packaged. The only material in existence which can do that and be used directly is - oil. Or natural gas.

Look up flywheel energy storage. It uses frictionless magnetic bearings in a vacuum to store large amounts of energy in a fairly safe way. It's been used in datacenters for years as batteryless ups. Low maintenance also because nothing in them really wears down except maybe the vacuum pump.

If the goal is building power sources, you absolutely have to factor that in. The Japanese pitch involves acquiring most mass on-site, and continual operation once built, so I would go out on a limb and bet that the fossil fuel consumption replaced by the Moon project would easily make up for any kerosene burned launching the parts.

(Financially, it literally must bring in more than the energy it cost to put it up or else the whole thing is superfluous.)

I'd suggest that while research is important, (I mean of course it is), it's certainly not a requirement for the Japanese in particular to do it in the context of this plan. If it makes sense at all, and flight rights are significantly boosted, than the research and development will happen.

In any case... Green rockets.

Scale Composites is using a "hybrid motor" that uses rubber as fuel. Or something. I don't know the details but if they mean it came from a plant, that's as carbon neutral as a space elevator will be.

Liquid oxygen and kerosene is also relatively benign. The exhaust is CO2 and water.

Hydrogen-fueled launch vehicles like the Space Shuttle and the Japanese H-II often use solid-fuel rockets as boosters due to the hydrolox engine's poor thrust. These solid fuel boosters combust fuels like aluminium with amonia perchlorate and leave a toxic powder as exhaust. The hydrogen is typically manufactured using methane. Then there are LVs like the Proton rocket which use hypergols which are also pretty toxic.

I'm very pro-rocket; space elevators and things are cool, and are something we should be researching and working toward, but we're not going to get there until we meet short term needs and grow a bit.

It'd be nice if everything was green, but space does not need to be uniquely green immediately; our most ambitious fantasies of the proliferation of space flight are like spit in the ocean compared to our total pollution output.