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#1 2004-05-03 15:12:19

deagleninja
Member
From: USA
Registered: 2004-04-28
Posts: 376

Re: Space Elevators.....How Soon?

Anyone been keeping up with space elevator developments or work on a related subject?

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#2 2004-05-03 15:14:18

flashgordon
Member
Registered: 2003-01-21
Posts: 314

Re: Space Elevators.....How Soon?

highlift.com seems to be down as of me checking a couple of days ago; liftport doesn't seem to have much that's new; it couldn't come soon enough much less anything else.

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#3 2004-05-03 15:19:40

Ian Flint
Banned
From: Colorado
Registered: 2003-09-24
Posts: 437

Re: Space Elevators.....How Soon?

Does anybody really believe that a space elevator will be built in our lifetimes?

I believe that it is entirely possible, but I also believe that we could have been on Mars in the '90s.  The technology will probably be ready within a few years, but will the political/business aspects be ready?

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#4 2004-05-03 17:08:04

deagleninja
Member
From: USA
Registered: 2004-04-28
Posts: 376

Re: Space Elevators.....How Soon?

Maybe my hopes a bit lofty, but I really think this just might be the answer to most of our progress problems. We say a lot here that no one is going to spend serious money on space till someone proves theres money to be made. Well a space elevator would make a lot of money. More importantly, it is a task that could be achieved by a large company or collection of smaller companies.

Imagine, if you will, this scenario. We use ion drive or sail technology to alter an asteroid's orbit till it orbits the Earth. Then we send up a small package to create atomic sized conveyor belts that move the carbon from the asteroid down the tether. Construction of the cable has begun. Meanwhile, construction of a space base, not station, takes place. This base has the advantage of being sheilded from the sun and its harmful solar activity by the body of the asteroid itself. It could even be an inflatable structure. The asteroid also sheilds the base from most, if not all, space debris in orbit. Now you have the cheapest means to transport material from the surface as well as a destination for tourists! An investors returns would start immediately.

At some point nations and the private sector is going to tire of paying so much to get materials to orbit. I think we will see at least an attempt at a space elevator like I have described in the next 15 years. Then getting to Mars becomes much more realistic. Infastructure, ladies and gentlemen, it's not just a fancy word, it's a requirement.

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#5 2004-05-03 18:39:20

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Space Elevators.....How Soon?

Oh its a lovely idea, thought of by other persons already of course, but it hinges on one technology that we don't have yet... nanotechnology. The only possible material that could be strong enough for the cable is a contiguous carbon nanotube "thread", that nobody is real sure is possible. The "big names" in the field of nanotech are split evenly if it can be done or not... I give it a 50/50 chance. Carbon nanotube composits you hear about on the news today are only nanometers long and are hard to make and even harder to make consistantly.

Investor return wouldn't be "instant" either, since the creation of a such a project would be massive... huge vehicle carrying a horrificly powerful propulsion system would be needed to put an asteroid into GEO, and then you would need a space factory able to make this fragile and finicky nanotube material, and you would need a base station and the cable cars and whatnot on the Earth end. No easy feat...


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#6 2004-05-03 18:49:57

rstones8
Banned
From: Orlando, FL
Registered: 2004-03-21
Posts: 37

Re: Space Elevators.....How Soon?

I would be extremely surprised if we see a space elevator in the next 15 years. Although it would make Mars much more convienient, I don't see us harnessing an asteroid with as-of-yet untested technologies before we go to Mars, which is quite possible with existing technologies. I believe a space elevator may come sometime after a permanent residence is established on Mars, as this would provide a great use for the elevator and huge economic opportunities.


"here are we, on this starry night staring into space, and I must say, I feel as small as dust, lying down here"-dmb

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#7 2004-05-03 18:52:50

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Space Elevators.....How Soon?

*points to above*

Nooo, no exsisting technology today can make a space elevator. There is a minimum amount of strength by weight that the cable must have. We aren't there yet. There is only one material in the universe that might do it, essentially flawless carbon nanotubes of arbitrary length, but these may or may not be possible to create. They are certainly a ways down the road.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#8 2004-05-03 19:15:11

Bill White
Member
Registered: 2001-09-09
Posts: 2,114

Re: Space Elevators.....How Soon?

A few years ago we had a lengthy space elevator argument here at NewMars.

To recap my views:

In looking at the economics, start with the need to recover capital costs. My big problem with space elevators was the level of utilization needed to recover the initial investment.

For example. $10 billion puts up a space elevator. Why not, its a nice round number. Higher costs make it worse, fast.

Assume 10% interest or rate of return to your venture capitalist. (They really, really like space and cut you a deal.)

Thus, we need to generate $1 billion per year in revenue just to pay the investor interest only on the cost of construction.

Our goal is $100 per pound, right? That means 10 million pounds of material must be transported each and every year just to pay the interest charges. $10 per pound means 100 million pounds must be carried just to pay the interest.

If the elevator costs $20 billion, those figures just doubled.

If I recall correctly, unless this thing is as busy as O'Hare airport, and run at a blistering operational tempo, you just are not going to have enough mass transported to make it viable.

If it is as busy as O'Hare airport, how many employees will you need to unload the container ships as they arrive. I assume the ribbon is attached to an oil rig type thing in the ocean and ships bring the cargo.

Okay, use robots. More investment and more costs to amortize. How much will these freight handling terminals cost? Salaries? Insurance?

$1 billion per year for salaries and insurance? That 10 million pounds per year just became 20 million pounds per year.

20 million pounds per year or 384,000 pounds per week or 55,000 pounds per day. Can the elevator carry that much?

At $10 per pound that is 550,000 pounds per day. We are talking a fairly significant freight terminal, the cost of which has NOT been factored in yet.

= = =

Related to this, bringing cars down the ribbon makes no sense. While they are coming down, nothign can go up. Build disposable cars and either incinerate them in the atmosphere or add heat shields and dump them in the atmosphere with de-orbit rockets.

Either way, more expense. Container ships will need to deliver cars on a regular basis.

Who will feed and house your passengers as they await their launch time?

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#9 2004-05-04 01:08:35

Josh Cryer
Moderator
Registered: 2001-09-29
Posts: 3,830

Re: Space Elevators.....How Soon?

Bill makes some very valid points. smile

When we had this discussion before, I essentially alluded to similar concepts, which is why I concluded that space elevators = US interstate system.

Exchange "space elevator" in Bill's post to "interstate system" and you'll see the same basic idea. Very big, expensive, projects require lots of input for them to be efficient. Taxpayers, etc.

Perhaps clark/Cobra/et al have a good argument here though for the military aspects of a space elevator (see, I'm not that biased!). smile

edit: check out the cost of the US Interstate System: http://www.fhwa.dot.gov/programadmin/in … state.html



Edited By Josh Cryer on 1083657042


Some useful links while MER are active. [url=http://marsrovers.jpl.nasa.gov/home/index.html]Offical site[/url] [url=http://www.nasa.gov/multimedia/nasatv/MM_NTV_Web.html]NASA TV[/url] [url=http://www.jpl.nasa.gov/mer2004/]JPL MER2004[/url] [url=http://www.spaceflightnow.com/mars/mera/statustextonly.html]Text feed[/url]
--------
The amount of solar radiation reaching the surface of the earth totals some 3.9 million exajoules a year.

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#10 2004-05-04 06:17:13

deagleninja
Member
From: USA
Registered: 2004-04-28
Posts: 376

Re: Space Elevators.....How Soon?

Bill why would we not want to bring equal or greater loads down from the asteroid than what we are raising? If a mining operation were established on the asteroid we should be able to lift 5 tons by lowering 10 shouldn't we? Our cable would have tracks on both sides of it.

I see your points about initial funding and returns. What I see happening though is someone spends 1 billion to move the asteroid using ion-drive probably. Once the asteroid is in orbit, they start selling shares of stock in their company and the rest of the money is raised. If planned out well enough, and assuming nanotech is up to the task in 10 years, it shouldn't be that expensive. Less money can be spent by taking more time. Take years to locate and gently nudge an asteroid and you'll find you don't need powerful rockets.

Couldn't our elevator cable be hollow and lower peices of it to a non-nano-sized machine working at the end of the cable to lock the links into place? If the automated machine at the end fails or dies for some reason, let it fall and walk another down?

I do think we actually need to assemble the elevator atom-by-atom. And I thought we did have a material strong enough to support the weight, maybe I misread.

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#11 2004-05-04 06:19:02

deagleninja
Member
From: USA
Registered: 2004-04-28
Posts: 376

Re: Space Elevators.....How Soon?

And wouldn't it be nice to see the international community get behind a worthy project such as this? That 10 billion figure could be split nicely amongst the 5 leading space agencies.

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#12 2004-05-04 06:43:27

Bill White
Member
Registered: 2001-09-09
Posts: 2,114

Re: Space Elevators.....How Soon?

Bill why would we not want to bring equal or greater loads down from the asteroid than what we are raising? If a mining operation were established on the asteroid we should be able to lift 5 tons by lowering 10 shouldn't we? Our cable would have tracks on both sides of it.

I see your points about initial funding and returns. What I see happening though is someone spends 1 billion to move the asteroid using ion-drive probably. Once the asteroid is in orbit, they start selling shares of stock in their company and the rest of the money is raised. If planned out well enough, and assuming nanotech is up to the task in 10 years, it shouldn't be that expensive. Less money can be spent by taking more time. Take years to locate and gently nudge an asteroid and you'll find you don't need powerful rockets.

Couldn't our elevator cable be hollow and lower peices of it to a non-nano-sized machine working at the end of the cable to lock the links into place? If the automated machine at the end fails or dies for some reason, let it fall and walk another down?

I do think we actually need to assemble the elevator atom-by-atom. And I thought we did have a material strong enough to support the weight, maybe I misread.

$10 billion was pulled wildly out of the air. Plan NOTHING off that number.

Even at that laughably small figure we are talking about needing to move lots of mass every day just to pay the interest. Space access lacks demand. There just aren't enough payloads to go up to justify a space elevator, today.

Down payloads? The cost is the opportunity cost for delaying another payload going up. A dedicated down cable makes no economic sense to me, until the costs of elevator construction fall by many orders of magnitude.

Down? Inflate a disposable heatshield and dump it in the atmosphere.

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#13 2004-05-04 08:21:08

Shaun Barrett
Member
From: Cairns, Queensland, Australia
Registered: 2001-12-28
Posts: 2,843

Re: Space Elevators.....How Soon?

I don't think the High Lift system required an asteroid. They were just going to launch a paper-thin CNT cable into orbit and lower one end down to a floating platform somewhere west of South America, in the Pacific.
    Climbers would then add more cables to that one, etc., until a very strong cable resulted.

    Everyone seems so pessimistic about the CNT cable.  roll
    But then, I suppose in 1904, people would have been just as pessimistic about passenger aircraft - probably more so.
    Arthur C. Clarke has written often about the main problem with predictions about the future. Most of the glaring errors have involved people being way too pessimistic about the rate of technological improvement.

    I suspect continuous CNT production will be achieved sooner than we think and I believe the first space elevator will be cheaper and arrive sooner than we think, too.
    If superconducting electric motors are used, climbers coming down will provide, by conversion of potential energy, most of the electrical power necessary for the climbers going up. A sufficiently strong cable may have several climbers going up and down at the same time.
    The first cable may well be tricky and expensive enough to require government assistance (I hope the military won't commandeer the whole thing! ) but the subsequent cables will probably be financially attractive enough to cause private companies to build them. This is dependent upon the first cable bringing about a large increase in space traffic, of course, which I think it will.

    Barring a sudden breakthrough in anti-gravity research (if it hasn't happened covertly already  :;):  ), I think the efficiency and elegance of the space elevator will ensure that it becomes the method of choice for reaching orbit. There seems to be no sensible alternative, at least at the moment. Unless you insist on us riding expensive, disposable, fiery Roman Candles to LEO forever!
                                                 ???


The word 'aerobics' came about when the gym instructors got together and said: If we're going to charge $10 an hour, we can't call it Jumping Up and Down.   - Rita Rudner

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#14 2004-05-04 08:51:31

deagleninja
Member
From: USA
Registered: 2004-04-28
Posts: 376

Re: Space Elevators.....How Soon?

Thanks Shaun for explaining what I meant better than i could have. To reach that $10 per pound cost we have been talking about Bill, you'd need a counterweight to 'pull' your cargo up. Do we need it, not exactly, but it would save a lot of energy further reducing costs.

Often the reason for some of our more fanciful ideas not becoming a reality is that there simply isn't the market. When we are talking about a cost reduction in the order of 100 times cheaper, I don't think it's fair to say that there would be no market. Many universities and institutions would love to perform experiments in space, but when they find out how much it costs, they are scared away.

Perhaps most interesting is the velocity boost outgoing spacecraft could get from the far end of the cable. Not only could our imaginary space elevator make affordable shipments to LEO, but it could also speed existing technology to it's destination faster using a sling-shot effect.

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#15 2004-05-04 09:09:11

deagleninja
Member
From: USA
Registered: 2004-04-28
Posts: 376

Re: Space Elevators.....How Soon?

Here are few links I've come across about space elevators. It doesn't see that far away from reading these articles:

http://www.space.com/businesstechnology … .html]2002

http://www.space.com/businesstechnology … .html]2000

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#16 2004-05-04 09:12:15

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Space Elevators.....How Soon?

Making CNTs is easy. Making long, uniform, flawless ones is hard. It will probably require the manipulation of individual atoms on an industrial scale, which is a long way a away even if it is possible. Its a chemical and physics thing, not an engineering issue like airplanes or trains.

I still don't see a large amount of business magially apearing to make the SE profitable; as Bill points out, the money ain't there to fly that often. Universities, the oft-cited customers, don't have that much to launch either, nor money to pay. There isn't a huge need for satellites either. Nor is there a big need for launches to leave Earth's orbit. Mining precious metals also makes little sense since flooding the market with them would drive down their costs, barring some large demand for a certain one for some reason.

Space station at the cable end? Why? There aren't that many tourists nor is there much research to be done. What kind of traffic are you referring to? I certainly don't see it.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#17 2004-05-04 09:43:08

deagleninja
Member
From: USA
Registered: 2004-04-28
Posts: 376

Re: Space Elevators.....How Soon?

Ok, lets assume for a moment that there is a SE and it can lift a pound for $100. I weigh 200 pounds so it would cost $20,000 to lift me to orbit. Now let's also assume that there is hotel at the end of the SE (asteroid or no). If they charge me $80,000 to stay a week in orbit then I'm still looking at only $100,000. There are hundreds of millions potential cusomers at this price range. Let's assume that 1 percent of the potential customers actually follow up with going through with it. We are still looking at about 2 million customers! With or without mining, solar panel power-plants, or satillite launch industry, there is still the tourism market.

Not to sound like 'Field of Dreams', but if we build it, them will come. A space elevator would be a lot less risky than riding a controlled explosion to orbit. As it stand now, only the wealthiest of corporations can afford telecommunications satellites, what about the little guys? There has to be ten times the amount of potential customers out there that would love to have their pet project in space, but can't afford it.

This is kind of off the subject, but space burials is an unexploited industry for the most part. Look how many thousands people spend in burial/cremation expenses. This is a huge potential market for our dream SE.

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#18 2004-05-04 09:46:00

Gennaro
Member
From: Eta Cassiopeiae (no, Sweden re
Registered: 2003-03-25
Posts: 591

Re: Space Elevators.....How Soon?

Like I've said before, I think it's better to wait with any serious commercialization of space (here the sublunar market isn't regarded as serious) until actual settlement of Mars has begun and then you can only expand as fast as incremental Terran demand, example for very precious metals, increase.
A scenario which in turn doesn't make it very worthwhile for private enterprise to become involved from the outset or even long term, although state controlled entities might find it promising to help finance space programs or make a small profit this way.
Mars is of strategic importance however, since the expansion and diversification of its settlements will by itself also open up the rest of the solar system. In the end capitalism will follow.

Personally, I'm a bit sceptical about space tourism. What if the space walk fad blows over or they for some reason won't come after all? You'll have empty and useless space hotels.
Better to trust objective demand for material goods. You can't base an entire new branch of the economy on the 'experience' sector alone.
After all, common folk maybe aren't as ecstatic about spaceflight as people on this board. At least it sounds pretty shaky to me.

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#19 2004-05-04 10:21:27

deagleninja
Member
From: USA
Registered: 2004-04-28
Posts: 376

Re: Space Elevators.....How Soon?

The majority of people on this forum are in favor of space development, but most wouldn't leave their comfortable lives for a life of hardship. The US wasn't settled by people that LOVED this country, but rather by people who wanted to get away from their native country.

Space isn't going to be developed by people you find on this forum. It's going to be done by people who want to get away, people like me. I am very odd as most of you have no doubt guessed. I'm agnostic, vegetarian and self-centered. I don't like capitalism. I loathe organized religions. I don't want to pay for a military like ours. I don't want this lifestyle that everyone seems to love shoved down my throat because I happened to be born here. In short, I want to escape.

If costs to reach space could be brought low by something like a space elevator, then the rich would go. With them goes a lot of labor to keep their toilets clean, backs massaged and hair cut. The wealthy would go just to be able to say they have. And where the wealthy go, the servants follow.

With toilet brush in hand......I am happy.

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#20 2004-05-04 10:43:30

Rxke
Member
From: Belgium
Registered: 2003-11-03
Posts: 3,669

Re: Space Elevators.....How Soon?

Heh, right on!

In another thread i stated i'd be happy to do the dishes ...on Mars.

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#21 2004-05-04 10:57:25

Bill White
Member
Registered: 2001-09-09
Posts: 2,114

Re: Space Elevators.....How Soon?

Lets work that $100 per pound backwards.

How big is the car? How often can it travel? Do some multiplication and that is the upper limit on what you can spend to build the thing.

50,000 pounds per day up-lift capability generates $5 million in gross revenue or $1.8 billion per year. If I did this right

http://ray.met.fsu.edu/~bret/amortize.h … rtize.html

this means you cannot spend more than $20 billion on the elevator (give or take a little) allowing NOTHING for operations expense.

Now, thousands of people want to ride. At 50,000 pounds per day that would be hundreds per day.

You need to build airports, restuarants hotels, etc. .  to handle those people.

Toilets? Where does all that stuff go?

= = =

At $100 per pound, you need to flow astounding quantities of people and goods through your terminal every day and the infrastructure to handle the cargo on the ground will increase costs significantly with little added revenue except some meals and shoe shines.

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#22 2004-05-04 12:11:23

deagleninja
Member
From: USA
Registered: 2004-04-28
Posts: 376

Re: Space Elevators.....How Soon?

And this isn't possible why? Sorry, I'm not as smart as you Bill, I missed something. Please put it in layman's terms.

As far as all non-SE activities go, our funder of the space elevator doesn't have to do that. Private companies already follow the tourists so I don't see that being a problem.

The space elevator could even double as a power plant for transporting of passengers to and from orbit by employing counterweights to each voyage up. Sending more cargo down, than what is going up, equals extra electricity.

I still think that an asteroid is the way to go. LEO is more dangerous every year due to leftover rocket and satellite debris. An asteroid sheilds you and your inflatable structures from nearly all debris. It is also a good source for construction material since the elevator is going to be so busy as you've stated. The cost to our SE owners could be $0 per pound when you are getting free electricity plus free metal ore.

Free is good.

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#23 2004-05-04 14:01:27

Bill White
Member
Registered: 2001-09-09
Posts: 2,114

Re: Space Elevators.....How Soon?

And this isn't possible why? Sorry, I'm not as smart as you Bill, I missed something. Please put it in layman's terms.

As far as all non-SE activities go, our funder of the space elevator doesn't have to do that. Private companies already follow the tourists so I don't see that being a problem.

The space elevator could even double as a power plant for transporting of passengers to and from orbit by employing counterweights to each voyage up. Sending more cargo down, than what is going up, equals extra electricity.

I still think that an asteroid is the way to go. LEO is more dangerous every year due to leftover rocket and satellite debris. An asteroid sheilds you and your inflatable structures from nearly all debris. It is also a good source for construction material since the elevator is going to be so busy as you've stated. The cost to our SE owners could be $0 per pound when you are getting free electricity plus free metal ore.

Free is good.

Even if you can build it, if you cannot do it and also make money, no one will.

If a 60 floor office tower can generate $1.8 billion in rent it is worth $20 billion (greatly simplified) no matter how much it cost to build. If your space elevator generates $1.8 billion per year in revenue and costs more than $20 billion to deploy, no rational person will do it.

A space elevator ain't nothing but a real estate investment. Either you generate positive cash flow or you don't.

= = =

PS - As for the asteroid. How big? Please don't miscalculate with orbital capture equations.

Remember that Mars probe that smashed into Mars because of English/metric confusion? Be a shame if that happened with the Earth and a gadzillion ton asteroid.

Since I believe US Space Command would go ballistic over a commercially available DH-1 - - I also believe there would be a whole lot of static about moving a big asteroid into LEO.

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#24 2004-05-04 14:21:15

Rxke
Member
From: Belgium
Registered: 2003-11-03
Posts: 3,669

Re: Space Elevators.....How Soon?

Hmmmm...

The initial cost *won't* be 100$/whatever, that'll take some years...

it will be more, but even if it's 7-500, (to GEO (!)) that's okay, customers will bite.
And once you have one cable, it can and will build others, *much* cheaper, bringing the overall cost down of cables as a whole...
It's all in the paper ( Google for "NIAC Phase II Final Report" ) on the cable, actually... operational costs and all...

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#25 2004-05-04 14:26:30

Rxke
Member
From: Belgium
Registered: 2003-11-03
Posts: 3,669

Re: Space Elevators.....How Soon?

Hmmm... scrap that, operational costs are not in the paper, only technical cost estimates: 6.5 Bil plusminus .5 bil... Now where did i read about it then? (Scratches head)

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