[Mika]

It is relatively hard to imagine solar panels using electrical energy driving something up 36000 kms. Transforming the electrical energy produced by those cells into a mechanical vibration sounds far more inefficient (at least to me). And loose vibrant energy in buildings raises hairs up.

But in any case, if that space lift was ever constructed, it would be monumental task and probably the greatest achievement human kind has ever done so far.

Mika

[Roanoke]

bit more significant than the Millenium Dome then ?

[Nuke]

i think i would just wrap the carbon nanotube cable with aluminum wire and just use the same kind of induction that maglev trains use. this would allow you to climb the tether without actually touching it, and you could actually achieve a greater speed so you could get to the station faster and wouldn't spend the whole trip twiddling your thumbs. this would also allow you to decouple at velocity relative to the cable so you can actually accelerate along the cable in the absence of atmosphere and have a nice bit of exit velocity when you disconnect. this would save of delta v when getting to the outer solar system.

still i think the real answer to utilizing space would be orbital fuel manufacturing. surely you can scoop up enough usable material from the solar wind, and process it into fuel and other essential items. surely there is hydrogen, helium, helium 3, deuterium and tritium there could all be gathered and separated. couldnt run chem engines but fusion reactors would love the helium 3, the rest could be used as propellants for electrical engines. scatter such automated stations across the solar system, and the requirement for disposable spacecraft would soon vanish. lunar and asteroid mining would produce the metals needed. linear accelerators would work well for lunar launches.

nanotube fiber composites coupled with hybrid rockets and air-breathing reusable first stage engines would be used for human transport to space. once all this infra structure exits i don't think you'd really need a space elevator. everything you need for space exploration would come from space, only requiring human transportation through the atmo. stop looking at the cost of shuttle missions as how much space costs. the shuttle is a brutally inefficient launch system.

when you look at the problem of deploying the cable, you cant just raise it from the ground, you'd have to lower it from the asteroid we use to anchor it (assuming asteroids are stable enough), which would mean it would have to either be manufactured in space, or lifted in sections. so you see the problem, installing it would require more space infrastructure, yet that infrastructure would so greatly reduce the cost of space exploration that it would be hard to justify the space elevator.

[BloodEagle]

It is relatively hard to imagine solar panels using electrical energy driving something up 36000 kms.

Isn't solar energy more efficient in super-atmospheric conditions?

But in any case, if that space lift was ever constructed, it would be monumental task and probably the greatest achievement human kind has ever done so far.

Until we discover and utilize a feasible FTL method, at least.

[Flipside]

Well, I think the Space Elevator will be one of the greatest physical/architectural achievements, it certainly surpasses big pretty piles of rock, but I think FTL will be a milestone in our mental evolution.

[Mars]

I honestly don't think FTL is possible. I think it exists somewhere around the same place as wee fairies and god.

[Flipside]

That, I think, is why it will be a milestone.

I think the actual act of going faster than the speed of Light is, as you say, impossible, however, that's not necessarily the same as leaving one place, and arriving at another in less time than it would take light to travel between the two. I have a lot more faith in pseudo FTL than true FTL.

[Mongoose]

The way I see it, out of all of these hyperdrives and warp cores and subspace nodes and other assorted technobabble that sci-fi has come up with over the decades, someone somewhere must have accidentally stumbled across something that could actually work.

[Nuke]

i said we should capture apophis for this, but everyone thought i was psycho

[Flipside]

Well, we've got about 25 years before it gets here, you never know, if we can get some kind of system in place like the elevator or the ramp, there may well be ships headed there, after all, it's not often you get a chance to look at an asteroid that closely.

Capturing and examining it may well tell us some interesting information about the origins of the Solar System, and possibly even help answer questions like 'was there a planet between Mars and Jupiter once?' (Last I heard, unlikely, since there aren't enough asteroids to make any planetary mass, but not impossible, since it cannot be told what was swept up by Jupiter and other bodies, and what got sent out on vastly eccentric orbits etc)

[Nuke]

well i was thinking about using it for an anchor

[Flipside]

Well, we'd probably only need a little bit of it to analyse, I suppose it depends if we catch it or simply land on it. If we capture it, then it's not a terrible idea, it saves getting a lot of bulk up there in the first place, you could prep a station on/in the asteroid and possibly even feed the line down from orbit, rather than try to raise it from the surface.

[Nuke]

lunar manufacture might be a better option though, not sure how readily available carbon is there.

[Kosh]

It is relatively hard to imagine solar panels using electrical energy driving something up 36000 kms.

Mika

It couldn't do it reliably, and even if it could you would need a huge number of solar panels. Nuclear is probably a better choice for something like this since it can supply as much as you need on demand.

Long term orbital and off world manufacturing and mining is the way to go, but first we have to get that crap into space before we can start doing things with it.

think i would just wrap the carbon nanotube cable with aluminum wire and just use the same kind of induction that maglev trains use. t

A lofstrom loop does the same thing, but using the maglev tech we have now.

From wikipedia:

A launch loop or Lofstrom loop is a design for a belt based maglev orbital launch system that would be around 2,000 km (1,240 mi) long and maintained at an altitude of up to 80 km (50 mi). A launch loop would be held up at this altitude by momentum of the belt as it circulates around the structure, in effect it transfers the weight of the structure onto magnetic bearings at each end which support it.

Launch loops are intended to provide a way for non-rocket spacelaunch of vehicles weighing 5 metric tons by electromagnetically accelerating them so that they are projected into Earth orbit or even beyond. This would be achieved by the flat part of the cable which forms an acceleration track above the atmosphere.

Economics

For a launch loop to be economically viable it would require customers with sufficiently large payload launch requirements.

Lofstrom estimates that an initial loop costing roughly $10 billion with a 1 year payback could launch 40,000 metric tons per year, and cut launch costs to $300/kg, or for $30 billion, with a larger power generation capacity, the loop would be capable of launching 6 million metric tons per year, and given a 5 year payback period, the costs for accessing space with a launch loop could be as low as $3/kg.[1]

[FUBAR-BDHR]

I remember reading awhile back about a way to generate electricity by using a tether in space to collect free electrons or something like that.  They weren't talking about small amounts of electricity either.  If that is possible it probably could be used to power the elevator and a lot more.   

[CmdKewin]

I honestly don't think FTL is possible. I think it exists somewhere around the same place as wee fairies and god.

"Any sufficiently advanced technology is indistinguishable from magic"

Arthur C. Clarke

[Androgeos Exeunt]

"Any sufficiently advanced technology is indistinguishable from magic"

Arthur C. Clarke

I thought FreeSpace 2 was magic when I first saw the trailer.

Just a question. Can the technology used in a railgun be used in a mass driver or this space elevator?

[Mika]

Isn't solar energy more efficient in super-atmospheric conditions?

Yes, but not enough to make the difference.

The difference can be calculated from AM0 (Air Mass 0) and AM1 (Air Mass 1), both are available for public use. The data contains a lot of different averaged measurement sets from the orbit (AM0) and from the equator (AM1). If memory serves, maximally a factor of 2 could be expected from that - but there is also need to protect the photovoltaics from more powerful radiation.

Mika

[Mika]

It couldn't do it reliably, and even if it could you would need a huge number of solar panels. Nuclear is probably a better choice for something like this since it can supply as much as you need on demand.

Oh, but then you meet again the Green movement which most likely protests against launching any nuclear thingies in space. Though they tend to forget that this stuff has already been done from the 1960s.

Mika

[Kosh]

It couldn't do it reliably, and even if it could you would need a huge number of solar panels. Nuclear is probably a better choice for something like this since it can supply as much as you need on demand.

Oh, but then you meet again the Green movement which most likely protests against launching any nuclear thingies in space. Though they tend to forget that this stuff has already been done from the 1960s.

Mika

I recall there was a huge uproar about 10 years ago or so about the Cassini and Galileo space probes being launched with radiothermal generators on board. It was total scare mongering and typical anti-intellectualism and anti-science from the environmental movement. Apparently they never realized that solar panels don't work when you get past Mars, not that such details are important to them.