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Space Elevators Could Be Lethal

kdawson posted more than 7 years ago | from the fried-by-van-allen dept.

Space 428

Maggie McKee writes, "A new study reports that passengers on space elevators of current design could be killed by radiation. Even traveling at 200 kilometers per hour, passengers would spend several days in the Van Allen radiation belts, long enough to kill them." Looks like the elevator scientists will get this one solved before liftoff.

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tinfoil hats (5, Funny)

Anonymous Coward | more than 7 years ago | (#16828458)

will tinfoil hats help?

No! Take off your tinfoil hats! (0)

Anonymous Coward | more than 7 years ago | (#16829222)

No, they'll only make things worse in this case!

The secret US DOD squadron of flying pigs with lasers beams on their heads can take care of the "space elevator issue" once and for all; unless they're from this important distracted by the shiny tinfoil hats!

Do your patriotic duty; shed your tinfoil hats NOW!

This message is brought to you by the letters T,H,E and M!

Re:No! Take off your tinfoil hats! (1, Funny)

Jeremiah Cornelius (137) | more than 7 years ago | (#16829418)

Lead Panties.

Who put all that junk in your trunk?

Re:tinfoil hats (1)

creimer (824291) | more than 7 years ago | (#16829360)

If you have a fear of heights, they might make great barf bags.

F1R$T P0$T!!!!!!!! (0, Offtopic)

gsonic (885510) | more than 7 years ago | (#16828466)

Suckaaaz

Re:F1R$T P0$T!!!!!!!! (-1, Flamebait)

Anonymous Coward | more than 7 years ago | (#16828578)

you fail it bitch

Aqua viva (5, Interesting)

TheSHAD0W (258774) | more than 7 years ago | (#16828502)

One of the most popular (and massive) items that will need to be shipped to orbit will be water; and water makes a good shield against radiation. Just make your passenger cars with a living unit inside a larger freight unit, and fill the gap in between with water. If you used filtered fresh water you could even have windows on both walls and be able to look through.

Re:Aqua viva (0)

CastrTroy (595695) | more than 7 years ago | (#16828632)

What's the point of transporting all that water up there if it isn't going to be drinkable once you get up that. All that radiation doesn't just disappear. I'm sure it would have some adverse effects on the water. You'd probably be better off lining the walls of the elevator with lead.

Re:Aqua viva (5, Informative)

maxume (22995) | more than 7 years ago | (#16828732)

Radiation does bad things to dna. It mostly just heats water. Ooooh, scary, somewhat warmer water.

Re:Aqua viva (2, Insightful)

camperdave (969942) | more than 7 years ago | (#16828834)

Don't worry about that. It'll be a solid block of ice by the time it reaches the top of the beanstalk.

Re:Aqua viva (5, Funny)

GIL_Dude (850471) | more than 7 years ago | (#16829164)

Right, and since it expands when it freezes, the people in the "living compartment inside" will not only be frozen to death, they will also be squished.

Re:Aqua viva (1)

pato101 (851725) | more than 7 years ago | (#16829740)

So light won't be able to cross the water afterall.

Re:Aqua viva (2, Funny)

isomeme (177414) | more than 7 years ago | (#16829936)

Better yet, line the insides of the cars with several layers of frozen pizzas; the passengers can eat them from the outside in as they pass through the radiation belts.

Re:Aqua viva (1)

Svartalf (2997) | more than 7 years ago | (#16828892)

Uh, it's not radioactive isotopes, it's ionizing radiation.

Isotopes go away. Pull the ionizing radiation away and the radiation goes too. Neutron flux is a different
story, but in that case, you're altering the atomic structure and causing isotopes to form...

Gah... Isotopes go == Ionizing radiations go (1)

Svartalf (2997) | more than 7 years ago | (#16829120)

Must be tired...must find caffeine...

Re:Aqua viva (5, Interesting)

malsdavis (542216) | more than 7 years ago | (#16828910)

Many water companies already treat tap water with gamma radiation to remove things like bacteria.

Radiation - unlike radioactive particles - won't cause any further radioactivity within water.

Re:Aqua viva (2, Insightful)

dattaway (3088) | more than 7 years ago | (#16829948)

Gamma radiation is cool, but neutron radiation rocks. It makes things radioactive long after its gone!

Hard water may be a problem here, but have you had to drink heavy water?

Re:Aqua viva (4, Insightful)

LWATCDR (28044) | more than 7 years ago | (#16828938)

"All that radiation doesn't just disappear."
Your right. I mean look at the lamp next to you pumping out radiation when you turn it off it doesn't just go away!
Actually most of the radiation in the Van Allen belts would possibly heat the water a little. a tiny amount might convert some of it to deuterium and maybe He3.
Another option would be to use really powerful magnets to shield the car. The radiation in the belts is there because it is charged and is earth's magnetic field keeps it deflects it. Can you say superconductors?

Re:Aqua viva (1)

voice_of_all_reason (926702) | more than 7 years ago | (#16829494)

a tiny amount might convert some of it to deuterium

You'll definitely have a carrer in Engineering once the Federation starts up. I'm pretty sure they frequently ran out of this stuff in all five series.

Re:Aqua viva (1)

bradkittenbrink (608877) | more than 7 years ago | (#16829704)

Why wait? [ufp.org]

Re:Aqua viva (1)

FooBarWidget (556006) | more than 7 years ago | (#16829996)

A recent issue of Scientific American explored the possibility of using magnets to deflect raditation. The conclusion was that it would require way too much energy for it to be feasible.

Re:Aqua viva (1)

callistra.moonshadow (956717) | more than 7 years ago | (#16828824)

Issue with water is that it's heavy. Really heavy. It will be a challenge to lift enough water into space for the shielding. :(

Re:Aqua viva (4, Insightful)

quizzicus (891184) | more than 7 years ago | (#16829116)

But how do you avoid the radiation on the way back down? Free fall?

Re:Aqua viva (1)

TheSHAD0W (258774) | more than 7 years ago | (#16829288)

Good point. Metals that have been solar-refined from asteroids, perhaps?

'Course that'll tend to block the windows.

Unless we start making transparent aluminum in space. ;-)

Re:Aqua viva (0)

Anonymous Coward | more than 7 years ago | (#16829372)

Back down? It's a one way trip, mi amigo. Until president bush fixes the overpopulation problem on a global scale we're busting at the seams.

Re:Aqua viva (1)

stungod (137601) | more than 7 years ago | (#16829518)

"On the way back down?" What's that supposed to mean? I can't stay there?

I'll just take my water and my covered wagon and settle up there...you guys can cook on the return trip if you like. I'll be busy testing zero-G alcohol abuse.

Feces? (0)

Anonymous Coward | more than 7 years ago | (#16829524)

n/t

Re:Feces? (2, Interesting)

TheSHAD0W (258774) | more than 7 years ago | (#16830024)

Actually, feces would probably be a huge commodity in space; it'd be invaluable as fertilizer for the farms.

And no, I'm not joking; if farms are at all feasible, you'd want them, not just to supplement the diet of the population in space, but also to regenerate oxygen from carbon dioxide.

Re:Aqua viva (4, Funny)

HolyCrapSCOsux (700114) | more than 7 years ago | (#16830000)

While it is up there, the water will be processed through the humans. The water used in the trip down will have a nice soothing yellowish tint.

Yeah... (1)

Dogun (7502) | more than 7 years ago | (#16828518)

because we're going to build a 150,000 mile long cable, tethered securely to the Earth's surface...

Re:Yeah... (5, Insightful)

COMON$ (806135) | more than 7 years ago | (#16829364)

Never underestimate the arrogance of man. Even if we didn't need the tether, we would still create it because we could. So your statement will join a long line of comments through history.

"Yeah - Like China will build a 4000 mile long wall."

"Yeah - We are going to build a tunnel under the English Channel."

"Yeah - We are going to dig a ditch to let boats cross America."

"Yeah - The Egyptians are going to build a gigantic pyramid that will still be standing in 4500 years."

"Yeah - We will propel a highly explosive cargo ship to the moon carrying people."

Re:Yeah... (1)

Mindwarp (15738) | more than 7 years ago | (#16829456)

I prefer to interpret that statement as "...because we're going to build a 150,000 mile long cable tehtered securely to the Earth's surface, but won't be able to work out how to shield the contents from radiation?"

Oh, the horror! (4, Insightful)

Vraylle (610820) | more than 7 years ago | (#16828520)

From TA: "it's going to make things a little more complicated and a little more expensive"

Everybody panic! Apparently, "a little more expensive" == "potentially lethal"!

I guess people should buy from Wal Mart instead of Target, since the latter is "a little more expensive". Obviously making a purchase at Target will kill you. I love sensationalist headlines.

Re:Oh, the horror! (1)

bcat24 (914105) | more than 7 years ago | (#16828786)

Word. I just wish I had mod points for you right now.

Re:Oh, the horror! (2, Insightful)

Meatloaf Surprise (1017210) | more than 7 years ago | (#16828832)

A new study reports that passengers on space elevators of current design could be killed by radiation. Even traveling at 200 kilometers per hour, passengers would spend several days in the Van Allen radiation belts, long enough to kill them."

Potentially lethal because of the radiation, which in turn makes it a little more expensive. NOT potentially lethal because its a little more expensive.

I really hope you were trolling

Re:Oh, the horror! (1, Informative)

Vraylle (610820) | more than 7 years ago | (#16828894)

I was neither serious, nor trolling. I believe in many cultures my original statement would be considered "a joke". Typically goes well with a sense of humor.

Re:Oh, the horror! (5, Informative)

A beautiful mind (821714) | more than 7 years ago | (#16828936)

Well contrary to the popular opinion, scientists aren't idiots, so they thought about the Van Allen radiation belts [wikipedia.org] long before any sensationalist headline came up with it.

Re:Oh, the horror! (2, Insightful)

Smidge204 (605297) | more than 7 years ago | (#16828884)

I like how you quote the LAST line of the article - the part that talks about solution discussions - completely out of context and then complain about sensationalist headlines.

The full, in-context quote is: "I'm confident that we can solve it," Jorgensen says of the radiation problem, "but it's going to make things a little more complicated and a little more expensive."

=Smidge=

Re:Oh, the horror! (0, Flamebait)

Vraylle (610820) | more than 7 years ago | (#16828952)

To summarize my earlier response: It's called a joke [wikipedia.org] .

Re:Oh, the horror! (0)

Anonymous Coward | more than 7 years ago | (#16829570)


I guess people should buy from Wal Mart instead of Target, since the latter is "a little more expensive". Obviously making a purchase at Target will kill you. I love sensationalist headlines.

When i was a kid, me an my pa used to hide outside a store at night an shoot at them yankees comin out.

It ain't for nottin they call it Target.

Jeez (2)

Profane MuthaFucka (574406) | more than 7 years ago | (#16828534)

Seems like this would be simple to solve. Shield the passenger cabin. The extra weight of the shielding doesn't make a damn bit of difference if it costs a penny for a quintilliton of cargo to orbit. Plus, you get to re-use the shielding. Those passenger cars to orbit are going to be like victorian rail cars. They never wear out.

Re:Jeez (1)

MindStalker (22827) | more than 7 years ago | (#16829194)

Electronics and a lot of other cargo you might want to send up would be effected by radiation as well. Just saying passenger compartments wouldn't be enough.

Of course article and Wikipedia all agree that adding complete shielding isn't impossible.

Re:Jeez (1)

Profane MuthaFucka (574406) | more than 7 years ago | (#16829884)

True, but electronics can be made rad-hard easier than people can be. Other cargo - depends obviously. Galileo absorbed a hell of a lot of rads orbiting Jupiter and survived. Those fields were far more intense than the radiation around the Earth. It seems to be a technical problem which has already been solved.

Water shield? (1)

A nonymous Coward (7548) | more than 7 years ago | (#16828554)

Haven't RTFA yet, but if mass is not the huge problem it is with rockets, maybe surround the passengers with a meter of water, or whatever it takes. If coming down is faster, for instance in capsules instead of crawling down the space elevator, or if down capsules are faster than up capsules, maybe the water could be cargo for the orbital endpoint of the space elevator.

Now I will go RTFA.

ya think? (4, Insightful)

Phroggy (441) | more than 7 years ago | (#16828564)

I thought the main idea was to send equipment, not people? If we can get one in place (which doesn't seem particularly likely any time soon), it'd be far cheaper to send tons of heavy stuff into orbit via a tether than via a rocket.

Re:ya think? (1)

RicktheBrick (588466) | more than 7 years ago | (#16829592)

I would think that it would be cheaper to use rail gun technology to send raw materials into orbit. I hope that we can send automated factories into orbit to collect the raw materials and assemble them into products such as communication satellites and solar collectors. If the elevator is made out of carbon nanotubes maybe it could also be a room temperature super conductor and than we could transport huge amounts of energy from the solar collectors we have in orbit.

Thank you, whistleblower!! (5, Funny)

cliffiecee (136220) | more than 7 years ago | (#16828576)

This is why the First Amendment is so important- to expose Corporate Greed! Greed which led space elevator manufacturers to produce elevators without the neccesary safety precautions. How many people have to DIE in the name of profit? How long will it be before space elevator travel is actually made safe? It should have been done BEFORE the elevators were even built, damnit!!

Thank you Maggie McKee, for planting a seed for the grassroots "Space Elevator Safety" movement!!

Re:Thank you, whistleblower!! (1)

R3d M3rcury (871886) | more than 7 years ago | (#16828802)

Agreed! We will immediate create a large government bureaucracy, the Federal Elevator Administration, whose job it is to verify that elevators are safe--whether they are taking you between floors or to orbit. All local elevator inspectors will be drafted into the new Federal Elevator Administration and be given jackets with 'FEA' in big letters on the back.

I'm suprised. (1)

AltGrendel (175092) | more than 7 years ago | (#16828598)

This is something I would have thought that the builders would have figured out. Also would it really be that bad? In the first place, I would think that the transport vehicle would be pretty darn fast at that point. Gravity would be less and the thing would gradually speed up as it neared the top. P.S. Why wasn't this a main article?

Re:I'm suprised. (1)

goatpunch (668594) | more than 7 years ago | (#16828792)

Why wasn't this a main article?
Because it's not news, this issue is always discussed when space elevators are mentioned, as in the Wikipedia article [wikipedia.org] .

As for speed, most designs have the space elevators moving pretty slowly, leaving the passengers in the Van Allen Belts for something on the order of days.

Re:I'm suprised. (1)

timeOday (582209) | more than 7 years ago | (#16829190)

This is something I would have thought that the builders would have figured out.
Since space elevators don't actually exist, I'm not even sure what it means to say they need better radiation shielding.

Re:I'm suprised. (1)

Jarjarthejedi (996957) | more than 7 years ago | (#16829344)

I wouldn't be surprised if they had already figured it out, considering the solution is from NASA's early days. Put a tiny little bit of shielding on the thing and boom, no more radiation problem.

Someone remind me why this is lethal since it has an impossibly simple solution, doesn't yet exist, and won't carry passengers without a good deal of testing? Seems to me that complaining about a simple to solve problem for a technology that neither exists no has been tested is stupid. Oh no! Some new drug may or may not cause cancer if it wasn't tested by the FCC before being put into production! Quick, arrest the company owners for putting me in danger!

Rockets? (4, Interesting)

Odin_Tiger (585113) | more than 7 years ago | (#16828600)

How much thrust would a rocket need to zip you through those sections if you waited to fire it until reaching, say, 500 - 800km? Surely by then you'd be far enough away from Earth that a little bit of push would go a long ways, compared to firing a rocket from the ground?

Re:Rockets? (4, Funny)

plover (150551) | more than 7 years ago | (#16828878)

How much thrust would a rocket need to zip you through those sections if you waited to fire it until reaching, say, 500 - 800km?

How much thrust could a rocket thruster thrust if a rocket thruster could thrust rockets?

No significant difference (2, Informative)

Stealth Potato (619366) | more than 7 years ago | (#16829838)

While there might be some small benefit, it would not be as large as you think. Gravitational acceleration is still very significant at 500km up.

Acceleration toward an object due to gravity is given by g = GM/r^2, where G = 6.67e-11 is the gravitational constant, M is the mass of the object, and r is the distance from the center of mass of the object. The mass of the earth is about 5.97e24 kilograms, and its mean radius is about 6.37e6 meters. Thus, the acceleration due to gravity at the planet's surface is approximately (6.67e-11 * 5.97e24) / (6.37e6^2) = 9.81 m/s^2.

Go up another measly 500 kilometers, and your new acceleration is approximately (6.67e-11 * 5.97e24) / (6.87e6^2) = 8.44 m/s^2. That's only a 14% difference; a very noticeable reduction, but not enough to have significant savings. Your rocket fuel wouldn't go much farther at all, at least when the goal of the space elevator is to reduce cargo costs by orders of magnitude.

Was this widely known? (1)

illegalcortex (1007791) | more than 7 years ago | (#16828624)

I'm a little suprised I haven't heard about this before. Has this been widely known among the space elevator set before now? My experience with space elevators has mostly been through the gloss-over-the-problems world of scifi. I thought the only real problem was in the construction and maintenance, not in the actual use once it's constructed.

Re:Was this widely known? (1)

Zerth (26112) | more than 7 years ago | (#16828814)

In most of the scenarios I've seen, it is taken as a given that you'd have a tank of water jacketing every passenger container, since water and food would be our primary exports(by weight).

As for going down, if we've started mining the asteroids, it'd make sense to replace the water tank/jacket with one of ore, instead of crashlanding the ore in the ocean. Alternately, until we ship up water-reclamation facilities, they could send wastewater back.

Re:Was this widely known? (0)

Anonymous Coward | more than 7 years ago | (#16829186)

I would assume you wouldn't send wastewater back, you'd send purification equipment up.

flame on! (1)

opencity (582224) | more than 7 years ago | (#16828626)

I've always wanted to be the human torch so sign me up!
Lack of caffine has rendered me unable to come up with other Van Allen refs from SF etc ...
Anyone?

The two rubs (4, Informative)

LotsOfPhil (982823) | more than 7 years ago | (#16828702)

This hasn't been an issue before because most astronauts don't get in the way of the van Allen belts. The Apollo astronauts went through super fast (escape velocity is 40,000 km/hr).
"For a space elevator travelling at the current proposed speed of 200 kilometres per hour, however, passengers might spend half a week in the belts. That would hit them with 200 times the radiation experienced by the Apollo astronauts."

The article says that you may not want to add shielding because of the added mass. Wikipedia [wikipedia.org] says that "an object satellite shielded by 3 mm of aluminum will receive about 2500 rem (25 Sv) per year." I don't know how this would translate for people going through the area, but 3 mm of aluminum doesn't weigh much.

Re:The two rubs (3, Informative)

InterGuru (50986) | more than 7 years ago | (#16829296)

2500 rem a year is about 6.8 rem/day. While occupational regulations are complex and depend on what type of radiation, they are the equivalent of 5 rem/year. See [state.ny.us] as an example. This means the occupants could not spend too much time in the Van Allen Belt.

Plenty of time (2, Insightful)

jfengel (409917) | more than 7 years ago | (#16828944)

Looks like the elevator scientists will get this one solved before liftoff.

You betcha they will. Compared to the problem of running a cable tens of thousands of miles straight up, and strong enough not to tear under its own weight, this sounds downright trivial. We're still a dozen orders of magnitude off.

Re:Plenty of time (1)

justasecond (789358) | more than 7 years ago | (#16829930)

"Dozen orders of magnitude"??? Oh reaaaally...

I'm no mechanical engineer (though my wife *is*), but I think freaking saltwater taffy is closer than that.

As for current nanotube tech., try *one* order of magnitude. (And no I'm not going to look up the references.)

Go Fast (1)

slam smith (61863) | more than 7 years ago | (#16828966)

Would it be possible to really fast through the belts?

Re:Go Fast (3, Funny)

MadCow42 (243108) | more than 7 years ago | (#16829276)

Sure, just eat at McD's for a month, and you'll go through all your belts in that timeframe. Supersize me!

MadCow.

Stupid headline (5, Funny)

nsayer (86181) | more than 7 years ago | (#16828982)

Space elevators can be lethal

So can regular ones [timesonline.co.uk] . Your point?

worse than Stupid headline (1)

bchernicoff (788760) | more than 7 years ago | (#16829310)

I didn't need /. to tell me that riding in an elevator that is climbing a 200,000km long ribon cable anchored to the sea floor and connected to a counter weight in geosynchronous orbit, while being shot at by a frickin'laser beam from the earth the whole time ostensibly to "power" the apparatus could be lethal. It goes without saying, mate!

Re:worse than Stupid headline (2, Funny)

creimer (824291) | more than 7 years ago | (#16829440)

Except no one mentions the giant sea monster that can come along and snap the cable at the anchor. Lethal radiation will be the least of your concerns.

space elevator - environmental impact (2, Insightful)

NATP (992108) | more than 7 years ago | (#16828988)

In the same vein -- Always wondered how you'd pass an environmental "impact" review for one of these things. What happens when your 20,000 nmi long cable to geosynch breaks -- or is intentionally damaged by the "bad guys" -- halfway up and 10,000 nmi of cable falls down to earth-- a cable 10,000 nmi would stretch from the coast of Ecuador to somewhere on the island of Borneo.... even bigger mess if it falls over land...

No ... just *impact* ! (0)

Anonymous Coward | more than 7 years ago | (#16829618)

Kim Stanley Robinson did a great job describing the (literal!) impact a falling elevator cable would have, albeit on Mars, in his Mars trilogy (Red Mars, Green Mars, Blue Mars). The turning of the planet causes the cable to wind around the equator; the forces involved have the cable falling so far beyond supersonic speed that all but the most temperature-resistant ingredients are incinerated by atmospheric resistance. Great trilogy, worth the read!

Re:space elevator - environmental impact (1)

Chaos Motor (974072) | more than 7 years ago | (#16829752)

From what I've read the cable would disentigrate before it landed.

Just use a Mass Driver (4, Funny)

MrScience (126570) | more than 7 years ago | (#16829022)

The solution, of course, is more speed! With a mass driver [wikipedia.org] , and 1000+ Gs acceleration, you too can zip right through that hazardous Van Allen belt in record time!

Regular elevators are fatal also (1)

davidwr (791652) | more than 7 years ago | (#16829106)

Before automatic safety breaks, crashing elevators killed more than one person. Even today, there are occasional fatalities, although AFAIK none from radiation exposure.

I've always wondered ... (1)

Gotung (571984) | more than 7 years ago | (#16829114)

Why does the space elevator need to be anchored directly to the surface of the planet? Wouldn't anchoring it to a zepplin like platform high in the atmosphere make the whole thing a lot easier to build? I mean that way you can cut out a sizable chunk of the "heaviest" part of the tether, and thus reduce the overall tension greatly. This would allow a much shorter tether since the spaceward end wouldn't need to extend nearly as far to hold up the drastically reduced weight.

You could use some high altitude balloon style craft to get cargo to and from the platform relatively cheaply.

Just seems like a better way to go than waiting for some mythical material that has the strength/weight ratio needed to support a fully to the surface tether.

Re:I've always wondered ... (1)

John Meacham (1112) | more than 7 years ago | (#16829268)

A zepplin can get maybe 50km into the air. geosynchronous orbit is 42,164km. that extra 50km isn't going to make much of a difference at all compared to the technical challenges of attaching something to a zeppelin.

Also, the thickest part of the cable is in the middle, not the ends. it is not pulling away from the earth at all, so the anchor doesn't actually need to support any weight, it is just nice to have a stable place to attach your elevator cars to.

Re:I've always wondered ... (1)

NATP (992108) | more than 7 years ago | (#16829270)

(tie it to a zepplin) is a variation of an idea that's been kicked around for a while as a gravity-gradient stabilized tether. Issues: Weather & Dynamics Most space elevator concepts assume you're tied to the earth to get the tension necessary to keep the thing from whipping around all over the place.

Re:I've always wondered ... (2, Informative)

NEOGEOman (155470) | more than 7 years ago | (#16829346)

It's the high-speed rotation and length of the cable that keeps it upright and taut. If you don't anchor the bottom of the elevator the entire thing will go flinging off into space. Fun for a while, but eventually someone will get upset about it.

Re:I've always wondered ... (0)

Anonymous Coward | more than 7 years ago | (#16830072)

As long as you're willing to fly up to meet it, you don't even need a static cable. The cable can rotate, coming down through the atmosphere to meet you and then zooming back up. This variant is sometimes called a "skyhook".

In fact, if you're really gutsy, you make the skyhook long enough to just reach the surface. The end of the cable will be moving horizontally at its lowest point, so it can just scoop you right up.

See, a tethered static cable isn't at all complex or dangerous compared to some ideas...

Sensationalist headline (1)

bkg_cjb (952573) | more than 7 years ago | (#16829134)

I thought that the advantage of the elevator was to transport alot of stuff for less money. Are most supplies really that sensitive to radiation?

C'mon, COMMON SENSE! (2, Interesting)

ShooterNeo (555040) | more than 7 years ago | (#16829168)

Why do people even waste their time on this idea. WHY DO WE NEED SPACE ELEVATORS?

For all the engineers here: why would you want to build a cable tens of thousands of miles long out of currently UNAVAILABLE materials (unobtanium) to slowly ratchet up one payload at a time? It's a horrid idea, and it STILL takes just as much actual energy to put anything in orbit...just it does so pathetically slowly.

The plan is to use PHOTOVOLTAIC PANELS to receive the energy being beamed from the ground. That is a patheticaly slow method of energy conversion considering the payload still has to receive the equivalent energy of being accelerated to several miles/second!

There's a simple and really OBVIOUS idea that has been on the drawing board for at least a decade. It would involve a heck of a lot less work, be likely much simpler and cheaper, and be flat out cool.

Instead of building just a few lasers to beam the energy, lets make a whole bunch of them and use the latest electrically powered pulse laser technology being developed for the joint strike fighter. Our spacecraft is just a payload module with stabiliers BOLTED to a block of inert material. A very short and simple linear accelerator kicks the spacecraft about half a mile into the air, high enough for all the lasers spread across the industrial plant infrastructure to 'see' it.

Pulses of light vaporize the fuel in a sequence such that the shock wave of superheated vaporized gas is planar : basically a rocket engine without needing :

A nozzle pumps, combustion chambers, volatile fuel, electrical systems, elaborate control systems and sensors, just enormouse amounts of hardware gets taken out of the spacecraft and left sitting on the ground. Sure, there's a LOT more delicate hardware left sitting on the ground...WHERE IT BELONGS. The laser launch system would be designed for almost continuous duty, launching one capsule after another all day long. Spacecraft would be MUCH simpler, and with a lower cost of launch could be made MUCH more cheaply as well. After all, why bother with all the checks and cleanrooms if you can send 10-20 Mars probes for the price of what 1 costs today? No need to shave every gram if launches only cost about 20 bucks a kilogram instead of about 1-10 thousand.

And finally, after testing this laser launch system by actually launching thousands and thousands of missions to find out what the REAL failure rate is, and gradually scaling it up to launch bigger, but just as simple, spacecraft we use it for manned missions as well.

  Seems like a no-brainer approach. I think the current planning for space travel is like trying to transport goods by horse and buggy across the continent on a massive scale when the same money could be used to install a railroad.

Re:C'mon, COMMON SENSE! (2, Interesting)

TheSHAD0W (258774) | more than 7 years ago | (#16829362)

Blasting something up with lasers is less expensive than using mechanical coupling. Though I agree, putting solar panels on the cars to power them is sort of silly. I'd run parallel rails up the beanstalk and let the cars tap the electricity.

There's something else you've overlooked: A car coming DOWN can use regenerative braking and feed power INTO the rails. If we're going to be mining for metals in space, we might wind up generating more electricity from the cars coming down than we'd spend in bringing cars UP. Net profit, even before selling the metals.

Re:C'mon, COMMON SENSE! (1)

naoursla (99850) | more than 7 years ago | (#16829680)

Nothing comes down the space elevator. Several payloads go up at the same time. Once the vehicle reaches the top, it becomes part of the anchor.

Re:C'mon, COMMON SENSE! (1)

TheSHAD0W (258774) | more than 7 years ago | (#16829962)

While it's under construction, yes; but once it had sufficient ballast mass, you don't think it wouldn't be utilized if the opportunity were there, do you?

Re:C'mon, COMMON SENSE! (1)

Control Group (105494) | more than 7 years ago | (#16830062)

Stuff had damn well better come down the cable, or the thing will deorbit itself. Angular momentum isn't free, and the outbound payload gains it by leeching it off the cable. Downbound payloads, however, give up their angular momentum to the cable. One of the tricks of the whole idea is to pretty much balance mass going up with mass going down, so as to minimize the amount of extra "station keeping" thrust you have to apply to the cable.

Re:C'mon, COMMON SENSE! (1)

ShooterNeo (555040) | more than 7 years ago | (#16830012)

That's the whole point. IF the elevator cable EVER fails : and don't kid yourself, ONE missile strike...not even a nuclear missile, something like a long range cruise missile with a payload of shaped HE, and the entire investment is lost.

And that's just deliberate sabotage or attack : accidental losses could cut the cable at any time. Once it's cut, we start over.

My proposed array of lasers on the ground, working in parallel (there would be a _LOT_ of them, at least 10,000 separately powered and housed lasing modules, maybe 100,000 to approach the output of the space shuttle) would be far less vulnerable. If one laser fails, you shut it down and fix it. You still have the other 9,999 working and available to launch something else.

So it isn't just cost : you can blast stuff into space over and over and over. You could easily launch enough cargo to establish a full industrial plant on the moon, or muster together a massive ship to actually go to Mars and stay there. Space power stations would be feasible.

And military applications : Star wars would actually be practical. We could put enough laser or microwave power beaming stations in space to dominate the Earth. ICBMS, and possible aircraft and missiles would be obsolete.

So the OUTPUT is also FAR higher, enough to actually make a real difference. Screw Space elevators, it's no better idea than using a giant cannon to get to space.

Oh, and one finally carrot : think about the sort of defense applications 'cutting', highly accurate weapons grade pulse lasers could be used for. Remember, I'm proposing basically taking the super high output pulse laser being developed for the Joint Strike Fighter, one that currently uses a secret breakthrough in technology, and making at least 10,000 copies - after redesigning it to be very cheap to manufacture.

That has obvious defense applications, since these lasers would be ubiquitous enough to deploy in military applications everywhere. Every new drone aircraft would be armed with one, there would be batteries all over the place such as in space and near major cities, ect, ect.

Re:C'mon, COMMON SENSE! (1)

ShooterNeo (555040) | more than 7 years ago | (#16830084)

Oh, and the deeply satisfying throaty roar of a rocket blasting off would still be there. It would also still be quite a kick in the pants to ride one of these capsules to orbit, just far cheaper such that many more of us could enjoy a trip. What would you rather do : be stuck in a tiny capsule for WEEKS as it SLOWLY ratchets up, or ride a shaking capsule with a nice solid deep hand of god crushing you into the seat as a couple of extra Gs of accelearation push you into the cushions. There'd still be a countdown and everything : but with less to fail (it would be like "gyros, check. computers, check, enough lasers Go : check : LAUNCH!) and you would not revise the design of the spacecraft but instead make many thousands of identical copies.

Re:C'mon, COMMON SENSE! (1)

unfunk (804468) | more than 7 years ago | (#16829508)

The theory is that there will be stuff coming down the elevator as well as going up it. "Eventually" (assuming lunar and asteroid mining is viable) there will be so much stuff coming down that the "up" travel is essentially "free" in terms of energy useage.

Re:C'mon, COMMON SENSE! (2, Insightful)

painandgreed (692585) | more than 7 years ago | (#16829870)

Why would we research unavailable materials? To make those materials obtainable. After they are obtained and the structure built, most of what you are bitching about will be trivial. You don't beam power up to the transport module. You have a power generator in deep space where it is free and plentyful and then you send it back down the cable to the surface where it can power cities. Along the way, the transport module can tap into that and use it for a constant acceleration for a realativly speedy ride up and down.

The rest of you post is simply the ranting of a man that doesn't understand the conversation. Right now, a space elevator woudl be the prefered end result because it would be the cheapest and easiest way to move things up from and down into of the gravity well. It's not being propsed as an immediate solution. If another method can be shown to be a cheaper end result, then I'm sure people will be looking at it. in the meantime, I suspect the vast amount of research that is going towards this project, such as the development of material needed for the tether, is coming from other research that has other purposes. Even if they stopped trying to devlop a space elevator, the same research would be carried out because I suspect that hardly any in the grand scale of things is being carried out soley for the goal of building a space elevator.

Your use of caps does not say much for your mental state either.

Mercury (1)

tocs (866673) | more than 7 years ago | (#16829176)

A tower that long could also fall on us. [amazon.com]

Other risks! (5, Funny)

StikyPad (445176) | more than 7 years ago | (#16829232)

Additionally, the space elevator is expected to be very tall, taking riders several miles above the surface of the earth where, experts say, they could fall to a harrowing death. And if that's not bad enough -- it turns out that if the earth were to suddenly stop spinning, the entire space elevator could come crashing back down to the ground!!! I, for one, will from now on refer to them only as "Space Elevators of Death!" in order to raise awareness about this potentially leathal issue!

Hybrid solution (4, Informative)

Fonce (635723) | more than 7 years ago | (#16829366)

Given that gravity won't be nearly as much of an issue at that altitude, a combination of shielding including water or metal (likely both) and increased speed seems to me to be the simplest route. All things being equal, that's probably the better solution.

We've made it through the Van Allens before, we'll figure out how to do it again.

And, anything can kill you, really, so long as it's an action. Space elevators aren't lethal in and of themselves. Organ failure due to blunt trauma, rapid depressurization, radiation poisoning; these can kill you. An elevator cannot. It's an inanimate object. Well, unless you're on acid. Then you're on your own, kid.

I smell problems (1)

p0ss (998301) | more than 7 years ago | (#16829396)

FTA


a cable stretching 100,000 kilometres from Earth's surface into space.


FTW (from the wiki)


A circular geosynchronous orbit in the plane of the Earth's equator has a radius of approximately 42,164 km (from the centre of the Earth) or approximately 35,786 km (22,236 statute miles) above mean sea level.


this article is poorly researched and inaccurate, the Van Allen belts have been taken into consideration before this, using payloads or various light elements as shielding, bremsstrahlung (this type of radiation) can be avoided.

Non-Issue

Re:I smell problems (2, Informative)

spun (1352) | more than 7 years ago | (#16829882)

The cable needs to stretch beyond geosynchronous orbit. The center of mass of the cable will be in geosynchronous orbit. As for the sheilding, the article simply says what you say: we will need some. Three centimeters of aluminum should do it. This is absolutely not news to anyone who has seriously looked into space elevator technology.

What we really need (1)

SDrag0n (532175) | more than 7 years ago | (#16829616)

is some dilithium crystals so we can make a subspace jump over the van-allen belt. Or mabye a anti-matter shield so that all the radioactive particals are distroyed with a violent bang. I know I would like some fireworks on my trip into space. They (the ambiguous they) should get to work on that as soon as they figure out how to make an enormous cable that stretches all the way into space.

Personally, I'd be more concerned about falling back to Earth. Having an hour to think about what it feels like before smacking the ground at terminal velocity sounds like blast to me.

Stupid argument (1)

gurps_npc (621217) | more than 7 years ago | (#16829698)

This is the same crap that astronauts have to deal with, nothing more.

Yes, radiation is OCCASIONALLY an issue, when the sun starts to get excited, so you have a shielded area that you restrict movement to when that happens. The sun telegraphs it's bad moves, generally giving us more than enough time to get to shelter. It is what they do on every Space Station ever created, and there is no reason they could not do the same on the elevator.

Well - DUH! (1)

M0b1u5 (569472) | more than 7 years ago | (#16829860)

Look - it aint rocket surgery is it?

Question: will passing through van allen belts without shielding cause harm to humans?
Answer: Yes.

Next time you need a stupid answer to a stupid question, I'll provide it free!

I simply can't understand why this would be news of ANY type! I mean, come ON - if it wasn't DEAD OBVIOUS, what would be?

So, the solution is to ensure that humans travel inside a tank, which is surrounded by 50cm of water, or 30 cm of polyethylene.

BIG HAIRY DEAL!

1) Take clean water UP.
2) Bring dirty water DOWN.
3) RINSE.
4) REPEAT.
5) Profit.

Scotty (1)

kawabago (551139) | more than 7 years ago | (#16829956)

Get those shields up before we hit the Van Allen belts or we're all doomed!

FUCKEr (-1, Troll)

Anonymous Coward | more than 7 years ago | (#16829992)

guys are usuaaly Encountered while was in the tea I BSD sux08s. What area. It is the Rivalry. While

Pondering vanAllen's belt (1)

JumpingBull (551722) | more than 7 years ago | (#16830078)

Which is a fine single malt scotch, AFAIK ...


The van Allen belts are where the ionic flow of the sun intersects the magnetic field of the earth. The charged particles spin around as they would in a cyclotron. This hints at a possible solution.
Suppose, for the sake of argument, that we use the stray field of the drive mechanism going up the elevator to produce a magnetic bubble to influence those charged particles to go elsewhere in the local vicinity. Now we have the shielding that we might need. Also, they are probably light elements, like hydrogen.
Just blue-skying it here for a minute, those charges look like a potential magento-hydro-dynamic generator -AND- if we collect the hydrogen, we *might* be able to make water along the way.

Clearly, I have made no calculations so this is highly suspect; interesting, but suspect. Still ...

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