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If ESA intends to get cheap access to space they should be looking at cheaper alternatives than a reusable space-shuttle. Even if the NASA model is made more economical, it's only going to be a fraction of the savings compared to looking at other alternatives

If you just want to race into space, just send a rocket with no payload up there. The lightest rocket [that can reach escape velocity] will, in all probability, win it.

Now if you want to send a person and a payload up there too, that requires a different set of rules.

Basically, it'll probably end up being more like Battlebots than NASCAR: there will be several categories of competitions.

(Then again, maybe NASCAR is like that too. I just don't watch it. "*singing* Alienating most of America..." -Conan)

Actually, if you want something that will get the most load up into space the fastest, the space elevator would take the prize hands-down.

They are.

Just have to get the actual material first. Only have aout 1.5 orders of magnitude to go before the nanotube-epoxy composite is strong enough...

Why isn't it NASA's main thrust yet? Gotta prove that it's possible first, with a real material.

I'm glad to see NASA looking at alternatives to rockets. This project, as well as the Space elevator are good ideas that if implemented could revolutionize space travel.

Does anyone have the numbers at hand to see if this makes a "beanstalk" feasible?

Yeah, with some refinement, of course. Give carbon nanotube research another 10 or 20 years and a ribbon-style space elevator would be possible. Take a look here. High Lift Systems, a research company under a large grant from NASA. They are proposing a very thin ribbon of carbon nanotube composite going about 50,000 miles out, or twice GEO orbit, that would be able to carry medium sized payloads. Cost would be around 10 billion dollars.

No thanks, I'd rather take the elevator instead. Cost to build $20B. Cost to fund (with 100% contingency) $40B total. You get a nice, smooth trip to orbit suitable for even medically challenged individuals. The estimated cost to launch 1kg would be $100-$200 instead of $40,000 via shuttle.

I think we'll cultivate a lot more good will if we send "oreos" to Mars. Especially double-stuff.

A space elevator wouldn't hurt either.

I used to think the space elevator was a silly idea, or at least a not-any-time-soon idea, and that we should tinker with tethers or J. Storrs-Hall's space dock idea in the nearer term. But I started reading the info (most of the technical issues are treated in essays in the "Downloads" section of the website) and it's remarkable how thoroughly this guy has considered every possible aspect or risk of the system.

We don't need a lot of new science and technology to do this. We need better nanotube manufacturing and we need an automated system that can shoot down flying garbage in LEO. Aside from that, it's just money and politics. It would mean the end of shuttle disasters, and every space activity would be 10x or 100x cheaper than it is today.

Interestingly, the space elevator guy has recently taken a position at this think tank where he says he'll have the resources to really put up a space elevator. I hope things work out for him. If he succeeds, we'll all be better off.

Sorry for the failure to appropriately curb my enthusiasm. I'll try to do better next time.

Yes, rocket propulsion is efficient in a chemical-kinetic energy transfer way, but not efficient if all other costs are taken into account. Use geo-thermal energy to power such a mag-lev launcher thing... I find that preferable.

While I was reading about the Space Elevator , I came across a neat article about something very similar to what you want.

It was a horizontal platform, very tall (kilometers?), looking like a series of "A"s, with a track running from the top of each "A" to the next. It would use electromagnets to generate thrust down the track, and the payload would achieve escape velocity by the time it reached the end.

After several minutes of Googling I couldn't find the link. Sorry 'bout that. Perhaps someone else recalls it?

I tend to agree. We would be much better off spending more money doing research on making a Space Elevator.

Just my $0.02

The revised, second-phase report, much advanced over the first, should appear Any Day Now. Just waiting for NASA approval. There's also a book that expands on the idea.

The web server was having troubles late last night, so slashdotting only provided the final straw. We'll be back.

According to this page (which I'm not sure how much to trust due to bias, but has similar figures to what some Googling turns up), carbon nanotubes buildable in the forseeable future have a theoretical tensile strength of 130 GPa (versus current laboratory nanotubes having a measured tensile strength that varies in the range of about 10 GPa to 60 GPa, according to Google) and have a density of 1300 kg/m^3 = 1.3E-3 g/mm^3 (or 1.3E-3 kg/m for a 1 mm^2 bundled nanotube cable, which is pretty close to your plugged-in value). Assuming all your equations are correct (I'm a little too fuzzy-headed right now to check in close detail, but they look perfectly fine from here), then the top end of what single carbon nanotube can do today is already near-or-barely-past the minimum tensile strength (about 63 GPa, which is both the bandied figure and what your own equations indicate after plugging in the new density) required to build a self-supporting orbiting cable. Individual nanotubes are a far cry from actual cables, but it's something to work with. If the 130 GPa figure is attainable, then the elevator should have a very respectable margin for payloads.

I hope they have a good relationship with Highlift Systems, because their FAQ is a copy of Highlift's .

Although with a space elevator it would be more cost effective and their plan only is asking for around $10 billion dollars (rather than the $100 billion in this article).

Of course that assumes that their budget is realistic and the engineering is really there (not just something they think will be easy to solve during the construction).

http://www.highliftsystems.com/convertedToHTML/nia c_pdf/contents.html

nice analysis !!

If the space elevator is feasible right now for only US$6 billion (less than half of NASA's annual budget), why aren't we building one ASAP and preparing to retire the shuttles?

Sounds to me the right thing to do -- invest in other companies to do the ground work, and see if it really is viable. If not they go bust -- Oh well. If it goes well, then great!

Yeah, a space elevator TO THE MOON. Realize something like this would take about as much material as the moon itself, not to mention the little problem of the moon rotating around the earth.

It isn't "TOO THE MOON," Einstein. It takes payloads to geosynchronous orbit, at which point it can be easily boosted to the moon. You already have almost all of the necessary speed, of course. Also, it doesn't take as much material as the entire mass of the moon. High Lift Systems has designed an elevator that uses carbon nanotube composites, and weighs only a few hundred thousand kilograms.

Please know what you are talking about before you post a vehemently critical comment. It makes you look like an idiot.

For an order-of-magnitude decrease in launch costs, reusables are the way to go. They do cost more to develop, though. There's a wonderful sequence in one of Terry Pratchett's books that I hope is appropriate here:

The reason the rich were so rich, Vimes reasoned, was because they managed to spend less money.

Take boots, for example. He earned thirty-eight dollars a month plus allowances. A really good pair of leather boots cost fifty dollars. But an affordable pair of boots, which were sort of OK for a season or two and then leaked like hell when the cardboard gave out, cost about ten dollars. Those were the kind of boots Vimes always bought, and wore until the soles were so thin that he could tell where he was in the city on a foggy night by the feel of the cobbles.

But the thing was that good boots lasted for years and years. A man who could afford fifty dollars had a pair of boots that'd still be keeping his feet dry in ten years' time, while a poor man who could only afford cheap boots would have spent a hundred dollars on boots in the same time and would still have wet feet.

Development should be "build a little, fly a little". I'm a big fan of the way Rotary Rocket approached things. If they had managed to get the cash equivalent of one shuttle launch, they would most likely be on orbit by now. But their business plan wasn't convincing enough, apparently. Sigh.

Of course you really want a 3-orders-of-magnitude decrease in launch costs, but for that you need a space elevator. And these cost *much* more to develop. :-)

What is your opinion on http://www.highliftsystems.com/ ?
It seems to be the way to go.

Do they get the money? HIGHLIFTSYSTEM.COM

This is a bit of a tangent, but...

This guy has written a report for NASA about the short term feasability of a Space Elevator, which would completely revolutionize access to space.

On the other hand, his english is sometimes not much better than CmdrTaco.

So, my question would be, does anyone know this guy, or know about what he's talking about enough, to tell us if this is at all feasible, and whether it would be a good replacement of our barbaric shuttles and rockets? S. Loisel

Compare this with the space elevator. The estimated initial cost ($10 bn) is about the same as that of the airbus. Govt. spending on the space elevator: $570,000. Benefit of the space elevator: It would possibly have an enormous impact on the destiny of mankind.

If only governments wouldn't be so shortsighted...

FAQ: Would the elevator be susceptible to a terrorist attack?

Yes- so is practically everything. An attack on the ribbon is unlikely because of the anchor station's isolation and the relatively small amount of casualties that would result. Its main protection is being so hard to get to, there is no way to sneak up on it. However if everyone has equal access to the benefits of the space elevator, there is substantially less risk.

The anchor is located in the equatorial Pacific 400 miles from any air or shipping lanes. The ribbon would also have restricted airspace around it. The ribbon and anchor would be protected like any other valuable piece of property, in this case probably by the U.S. military.

Hmm... I think it's too idealistic. NASA has to keep in secret even the date of Shuttle lifts. How they are going to protect the system functioning 24/7 in a place surrounded by see?

Any ship with 200 miles missiles can come to 200 miles distance and hit it. They cannot do wider security zone with today's international laws, but if they can (let's say 400 miles then it will be a matter of time to see a ship with 400 miles missiles hitting the target.

I think before such project will be built they have to improve somehow the quality life of international community. USA govt should begin to respect UN. UN should work more actively against potentially aggressive goverments, even against potentially unstable goverments. That may mean a completely different system of international laws than we have now.

So, if the idea to bring the highlift project alive will help to improve the international community - we should do it. Otherwise, it's danger for the current world of aggresive animals.

RTFWP! 1-5 years from today for technology to mature and test, 6 years to construct.

I'm appalled at the lack of imagination shown by most of these posts.

First off if you read the PDF (15M) report to Nasa prepared by Bradley C. Edwards to satisfy the requirements of his $500 000 grant you will readily see that this is totally feasible.

Next check out the website - where they are calling for people to express interest in working on this project. They expect to be hiring in the next year or so. You'll also see that serious people are taking this seriously. Do you want a job?

Next understand that $17B is not very much money. Considering that BP just spent $6.7B on a oil company in Russia and has plans for more purchases.

I meantion BP because they have a plan to move beyond oil.... BP Solar is BP's attempt to become a broader energy company (check out their new sun logo) instead of an oil company. The High Lift systems news page says: -

BP Solar - a subsidiary of British Petroleum, currently doing $300M in annual sales. Our discussions have focused on BP's interest in using the SE for deployment of a solar energy satellite. Several items that came up included possible collaborative efforts, the performance of our system and the possibility of BP using our system. They are considering writing a letter of endorsement

If BP with the cash they have can throw $6.75 B at Russia they could, over 5 years, finance a large share of the Space Elevator. Who needs the Government? In fact Nasa would make sure it costs more to build than it should. Nasa is a bureaucracy, not a business, and is ill-suited to the sort of cost control required of economically viable business decision. Only communists would argue that a Space Elevator should be built and controlled by government.

What would BP Solar do? Build Power Sats....

These are High Lift's vision for the main use for the Space Elevator. Imagine a fleet of these beaming power to anywhere on earth. Every country on the planet could get cheap electricity without the huge national grid infrastructure required now. Without the huge investments in time and resources to build power stations - and without the fossil fuel use.

Use your imagination.

These ideas have been the subject of SF for decades - but the Space Elevator is now possible due to those nifty Carbon Nano-tubes.

When your imagination focussed by the reality of this thing actually being built in the near term (5 years) everything changes - and it'll change for us not our children. It'll change our careers.

Imagine this - an electric airplane that is powered by a Powersat beaming microwaves to it. No fuel to carry, super efficient travel - and at what speeds?

These guys are planning for the Space Elevator to be operational SOON - they have realistic timelines.

What I want to see here is some discussion of the uses that could realistically be made of a space elevator. We're the generation that will built it, use it and be changed by it. I like the parallel to be made with electricity, or flight, or the steam engine - in the early stages everyone probably dismissed it - and the world changed despite them.

What would you realistically (with a nod towards economic viability) do with the low launch costs they're projecting - $10/LB...

Ideas anyone?

No that is not true. If the cable starts out small and you transfer mass to the end of the cable durring constuction you don't need an asteriod or a space station. Here is the report that details the plan for building this first space elevator. The cable that they are planning is very small compaired to what has been talked about in scifi. They have a whole section talking about costs of the project, at least read a little about what they plan to do before you claim that it will cost too much.

josh

The Highlift Systems FAQ says the US military will probably have to protect it. Which might mean fighter planes based off carriers flying around the ribbon to prevent any other aircraft or any ships from getting too close.

The section of their FAQ that discusses the problem of large electrical currents generated by long space tethers was really interesting...

Would it be feasible to create a tether to low-earth orbit for the express purpose of generating electricity? I wonder how the cost would compare over the long-term to other low-cost sources like wind and nuclear.

Also, could this possible create drag in the solar wind and slow the Earth's rotation? (most likely another stupid question)

Not stupid at all, accurate actually. See their FAQ .

The second paragraph ends with:

The extra angular momentum is stolen from the Earth's rotation; we will have to worry about this effect slowing down the Earth and making the day longer if we ever decide to ship Australia into space.

It's kinda neat that they used Australia as an example (I read their FAQ a few days ago, before this decision about putting it near Australia was published; they didn't change the example for this recent news).

OT: the fortune at the bottom of the page is very amusing: "Mr. Spock succumbs to a powerful mating urge and nearly kills Captain Kirk." -- TV Guide, describing the Star Trek episode _Amok_Time_

The simplest explanation of the space elevator is that it is a cable with one end attached to the Earth's surface and the other end in space beyond the geosynchronous orbit (35,800 km altitude). The competing forces of gravity at the lower end and outward centrifugal acceleration at the farther end keep the cable under tension and stationary over a single position on Earth. This cable, once deployed, can be ascended by mechanical means to Earth orbit.

Which just goes to show, if you're asking on Slashdot, then you're either too lazy or too stupid to find out yourself.

FYI, the figures I gave a not pulled out of thin air, but come from the already mentioned a few times Highlift Systems Site. Do a bit of reading and come back enlightened.

By the way, whose "best guess" is this 5m radius?

(Hint?) Science fiction books do not science make.

HighLift Systems has a design of a 100,000 km long cable that has a density of 7.5 kg/km. That is 750,000 kg total for the cable. Consider the enormous amount of tension that such a cable must withstand. There would be very little difference between a cable that can only support itself and a cable that can support a payload.

I suggest you read the HighLift Systems website. They have a lot of really good information:

http://www.highliftsystems.com/

Tethers ( 1, 2, 3 ) attached to counterweights can be used to transfer spacecraft from one orbit to another. The first tether has an orbit that skims the atmosphere, where a craft catches and connects to the end of the tether. The craft is lifted into low earth orbit and subsequent tethers help it to reach escape velocity. Using the tethers takes energy out of the orbits of the counterweights, some of which can be put back by using the tethers for descent as well as launch.

J. Storrs-Hall (once moderator of sci.nanotech) envisioned a space dock, a linear motor suspended 100 km above the ground that accelerates spacecraft to an elliptical orbit. He computes an amortized cost of reaching low earth orbit of 42 cents per kilogram. From the elliptical orbit, it's a relatively small safe step to escape velocity.

A space elevator ( 1, 2 ) is an excellent long-term solution. A cable is hung from a weight in geosynchronous orbit, reaching down to the Earth's surface. The elevator climbs the cable, carrying a craft. When it reaches GEO, the craft detaches and spends only a little fuel getting to escape velocity.

Tethers and the space elevator require novel materials for strong cables, probably using carbon nanotubes. The frame to hold up the space dock is in compression, and something we could build with little or no advance in material science. Any of these alternatives would be vastly cheaper and vastly safer than putting human lives on the noses of fuel tanks subjected to unreasonable speeds and stresses.

It would be a money sink that would never pay back its construction costs

Complete bollocks. Specficially, if it cost $20G to build (they say $10G), it need only make $2G/a to handily beat bank loans and stuff as a payback means. So double the $100/kg lift costs to $200/kg, big deal in the face of the $10,000-$30,000/kg it is now. $2G / $100/kg extra profit == 20Mt/a, 55,000t/day, 2300t/hr, a 400t load every 10 minutes.

Need to halve that load? Triple the price instead of doubling it. Or use the elevator to build more, and amortise the costs between them.

It would be the worst sort of governmental monopoly

And we don't have one now? Go ahead, build your own Saturn V or Energia-Groza, be my guest.

Once they have half a dozen of these up, owned by 3 or 4 countries or consortia (I'd guess USA, EU, China, Russia, India, Brasil), that starts to break down anyway. If Australia wanted to build the first one, that would cost us $10,000 a head. If it built the 8th one, maybe $500 a head and every Australian gets their first 2kg hauled to space for free. If the people living in Perth pooled their gree kilograms, we could loft a 3000 tonne satellite.

It would be The Definitive Terrorist Target

Ever tried to hit something a meter wide from 10 km away? With defenses on the elevator shooting back at you and at your shells?

Clearing a corridor 10km wide around this would be no problem, and keeping it clear with SDI technology (near the ground, a perfectly ordinary Vulcan radar-guided cannon would do the job) relatively simple. Can you outfly a laser? Could your aircraft or missile survive several hundred unexpected megawatts of microwaves tuned to some vital dimension? How about a smart remote-targeted crowbar dropping in on you from LEO at mach 20?

It would be a murphys-law magnet

Any concievable replacement would be worse.

And that's even before an orbiting piece of space junk slams into it.

It would have to be a clever piece of space-junk, smaller than a peanut and yet more destructive than a nuke. You haven't had a look at the design, have you?

If they were kind enough to put the elevator up on the Equator (not necessary, but it helps), it (or more specifically the defenses on it) would actually make a pretty good street-sweeper for the space industry.

And it would be a catastrophe waiting to happen, when (not if) it snaps and rains megatons of carbon cable down upon the ground below.

That statement just betrayed your complete ignorance of how the elevator would work.

Of the 100,000km length, less than 100km would be in atmosphere. Take what is presumably the worst case: the cable snaps about 50km up. 50km of cable fall to earth, the top 30km or so burning up on re-entry, the balance stays in orbit. That's right, losing 0.05% of the cable makes very little difference to its orbit. Soon the lost 50km is replaced by shipping it out along another cable and unreeling it off the next segment above the damaged one.

But what about the bottom 20km? Even if it were heavy (did you read the line saying `paper-thin?'), it would fall into the ocean. Even if they anchored it at, say, Kununurra (in the far north of Western Australia) and it were heavy, you'd still only lose a stripe of desert a few m wide and 20km long. Big deal.

Now, important step, visit High Lift Systems and RTFM. Then come whinging back here.

Quote, The space elevator would essentially allow the world to participate, time to found the Open Space Institute? (-:

Perhaps they should have priced it in terms of Shuttle missions. The shuttle has launched over 100 times, at a typical cost of about $500M per launch equals roughly $50G, so their elevator would be priced at 80 shuttle missions or under 4/5 of the money spent so far running the Shuttles.

Speaking of which: in terms of fatalities per passenger mile, they're much safer than jetliners, orders of magnitude better than your car. OTOH, you car doesn't cost billions of dollars to replace if you write it off. OT3H, I'd be really happy if I got that many miles out of any car, ever. (-:

While the initial investment of $7-10 billion may seem a bit steep, a space tether can lift payloads to orbit at about 1/100th the cost of current heavy lift rockets and shuttles.

I mourn the loss of our astronauts, and pray for their families hoping they find comfort in that their sacrifice was most noble and unselfish.

she meant elevator to the moon, right?

I'm afraid you are mistaken my /. friend. You are forgetting one very important thing:

Nanotech will bring in the next 10 years - mass produced carbon nanotubes.

This advance alone will revolution industrial design more than anything in the last 200 years. Among the wonder made feasible and affordable by carbon nanotubes are very cheap access to space with not only very lightweight (read cheap $/lb to orbit), but novel structures like Space Elevators.

As far as morphing into any shape - disputing this means you also dispute that molecular assemblers are also impossible or at best very difficult in the next century. Do not forget Moores law, and that we can expect computers on the desktop running at Petaflops within 20 years. That kind of computer power will allow us to make incredible strides in protien folding and subsequently molecular manufacturing.

Planet P Blog - Liberty with Technology.

Launching to Mars from the Moon would be cheaper, since the force needed to break the moon's gravity is a[]lot less.

Sending people into space is a complete waste of money and resources at this point. We should take up manned missions when space is so cheap that it just doesn't make sense to send equipment up there without them.

How much did you donate to getting a space elevator built then? $zero? You could at least buy the book instead of just pontificating!

• Starwars I: $250G
• Starwars II: $200G (probably more IRL)
• Pasting Iraq: $200G (ditto)
• Pasting Afghanistan: $3G
• Gulf War: $80G (2002-USD plus many times that in total by others)

If not let them in on the space station, why not start funding some private sector research into propulsion and lift mechanics. If somebody could come up with a way to lower the cost of a launch from tens of millions down to tens of thousands. I'm thinking here of Highlift Systems then it potentially could be this century's California/Alaskan gold rush.

RTFF

I wonder how hard it would be to pull that asteroid to earth orbit for mining or as an anchor to a space elevator, a la the [almost] original concept by Arthur C. Clarke (later designs use a man made anchor).

If we can mine useful materials, we could build some cool, big ass stuff probably cheaper than we would carry all that weight from the surface.

It's not realistic to think that a rocket can launch the cable. It's going to be massive - billions of metric tons. No rocket could lift that.

Actually, that's not the case.
See here.

Environmental Impact: In any large program the environmental impact must be
considered. We are examining the impact of a catastrophic failure of the cable and
how to mitigate this occurrence. If the cable comes down the worst case is that it
will burn up on re-entry. The influx of material is small compared to natural infall or
our current space operations. The debris will be most likely be large pieces of cable
but may include individual nanotubes. Our initial tests show that carbon nanotubes
will not dissolve in lung fluids. The next test is to understand the inhalation rate and
possibility of damage once inhaled.

If you read the FAQ, you would know that a 1km-long section of the cable would weigh in at a whopping 7.5 kg (i.e. it's lighter than tissue paper). Yes, if you calculate mass alone, it holds a substantial amount of potential energy. But that energy is dispersed into the air across a HUUUUUGE surface-area to mass ratio, and the result is it would impact the surface with about as much force as a few tons of loose feathers or ticker-tape confetti.

Big mess? Yes.

Tidal Wave? More like a ripple.

• Yes, a crack across the ribbon would be bad. But you can make the ribbon be several loosely-coupled parallel sub-ribbons that give a little but don't separate completely when one of them breaks. And yes, you'd have to repair it pretty quickly. At altitudes with lots of space debris, you can make it extra-wide and extra-strong for redundancy, and add only a fraction of a percent to the mass of the overall cable.
• Lightning strikes can be avoided by going to the right place on the surface of the earth. Parts of the equatorial Pacific receive lightning strikes less than once every few years. And a mobile base station could move the bottom of the cable out of the way of small storms. There are also possible lightning rod approaches for typical storm altitudes (weather balloons, for instance).
• Shorting out the ionosphere -- given the sheer length of the tether, even if it were as conductive as gold, the resistance between the ionosphere and ground of tens to hundreds of thousands of ohms.

So yes, there are many challenges to overcome, but they all, fortunately, seem surmountable.

The reason is sheer length -- even if the cable were as conductive as gold, it would have a resistance from the ionosphere down to the Earth's surface of tens of kilo-ohms (see same paper).

The minute I saw it on slashdot, just like the last time, I knew people would go into the "this is just impossible" mode without at least giving it a shot.

Ok, I'll bite. READ THIS (warning, it's a pdf file), and once you do, say it again. I'm not saying this paper is wrong, but it's enough information to realize that there's no one thing preventing it form happening. Not even money, as it would all cost about the same as the International Space Station. The one thing that doesn't exist as of yet is the nanotube wire, which feasbility is clearly only a matter of time. So if the existance of the Space Elevator depends on the existance of a 90,000 Km long nanotube wire (the fabric industry is used to threads this long, again, read the paper), then there's no doubt that it will become a reality.

The space elevator is doing for me what the apollo program did for my parent's genration: It's giving me an overdose of inspiration.