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"Ballooning" Spiders Use Electrostatic Forces To Generate Lift

samzenpus posted about 7 months ago | from the when-spiders-learn-to-fly dept.

Science 213

KentuckyFC writes "Many types of small spider release threads into the air which then lift and carry them significant distances. Biologists have found them at altitudes of up to 4 km. The conventional thinking is that the threads catch thermal air currents which then carry them away but this does not explain how spiders perform their trick even when there is little or no wind. Now one physicist says the explanation is the atmosphere's natural electric field which has an average downward-pointing magnitude of 120 Volts per metre. He calculates that a strand of silk need only gain a negative charge of around 30 nanoCoulombs to lift a spider. That explains how the spiders take off on windless days, how they reach such great heights and how several strands can lift heavier spiders of up to 100 milligrams."

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213 comments

Obama, GOP look at shutdown in a week (-1)

Anonymous Coward | about 7 months ago | (#44923757)

The fiscal year ends next Monday at midnight, and there will be a shutdown unless Obama and the Republicans agree to a new spending plan and resolve a dispute over Obama's health care plan.

Some GOP members say they will not approve a new spending plan unless it de-funds "Obamacare," though there is division within the party over this tactic.

AGW FRAUD!!!!!!! (-1)

Anonymous Coward | about 7 months ago | (#44923765)

Hey morons why aren't you talking about the GW fraud?

http://www.latimes.com/science/la-sci-climate-change-uncertainty-20130923,0,791164.story

"Since just before the start of the 21st century, the Earth's average global surface temperature has failed to rise despite soaring levels of heat-trapping greenhouse gases and years of dire warnings from environmental advocates. Now, as scientists with the Intergovernmental Panel on Climate Change gather in Sweden this week to approve portions of the IPCC's fifth assessment report, they are finding themselves pressured to explain this glaring discrepancy. "

Imagine that. Scientists being asked to explain why their science doesn't seem to be working out. The nerve.

"Though scientists don't have any firm answers, they do have multiple theories."

Uh huh.

Re:AGW FRAUD!!!!!!! (-1)

Anonymous Coward | about 7 months ago | (#44923793)

At The Center For Global Warming Awareness

Scientist: Ok. Input the conclusion.

Drone 1: Whut?

Scientist: I said, input the conclusion!

Drone 1: We don't know the conclusion yet. I haven't put the data in.

Scientist: The data doesn't MATTER! The concensus is the earth is warming at an alarming rate and it's caused by MAN!

Drone 1: That's insane! How can you reach a concensus before the data is analyzed?

Scientist: Because we're SCIENTISTS, AND YOU'RE NOT!

Drone 2: Just do it dude.

Drone 1: Fine!.... There! You happy now?

Scientist: YOU ASSHOLE! I am NOT a LYING DOUCHY DOUCHEBAG! ARRGH!

Drone 1: Aw man! I think he just had a heart attack.

Drone 2: Yea dude. But you know what?

Drone 1: Whut?

Drone 2: He's dead Jim.

Drone 1: Heh. Star Trek reference. That's funny.

Posted by: Drones who work for douchebag scientists

Re:AGW FRAUD!!!!!!! there is no (-1, Offtopic)

RichMan (8097) | about 7 months ago | (#44923851)

"global surface temperature" is not global temperature. Global temperature includes deep sea temperature and high atmosphere temeperatur. It is very easy to heat and cool air. Heating the deep ocean takes decades or longer.

Stop looking at it from a local or even surface point of view. Vertical air circulation is accelerating, this is what causes the arctic ice to close up. Cold air up north does not come from up north, it comes from high in the atmosphere, it just happens to "fall" down up north because that is where the weakest counter push "up" is.

There are dynamics here we are still looking at and learning. Surface temperatures are the thin single layer of the onion when there are many layers of the atmosphere and many layers of the oceans to look at as well.

Re:AGW FRAUD!!!!!!! there is no (-1)

Anonymous Coward | about 7 months ago | (#44923951)

"There are dynamics here we are still looking at and learning. Surface temperatures are the thin single layer of the onion when there are many layers of the atmosphere and many layers of the oceans to look at as well."

That's funny, I thought there was a consensus and a 99% certainty and being a skeptic was worse than denying the holocaust, etc.

Re:AGW FRAUD!!!!!!! there is no (-1)

Anonymous Coward | about 7 months ago | (#44923961)

Here is an example that will help people relate to why part of the earth are cooler, even though the earth is heating up. Imagine you come home on a cool day and your furnace is off. You turn it on but the registers are closed in the bedrooms. The hot air then all enters only the living,/dinning room/ kitchen areas. This pushes all the cold to the bedrooms so he temperature there actually drops. In fact, while it was cool there before, icicles actually may start forming. The more you turn up the heat, the more the cold is forced into the bedrooms and the icicles keep growing. I'm sure many of you here have seen this effect in your own houses. We have models that demonstrate this too!

You stupid bunch of fuckwads.

Re:AGW FRAUD!!!!!!! there is no (0)

Anonymous Coward | about 7 months ago | (#44924009)

This is impossible because the earth is only 6000 years old.

Re:AGW FRAUD!!!!!!! there is no (0)

Anonymous Coward | about 7 months ago | (#44924847)

DNFtT

Yes, But... (2, Funny)

Atmosphereum (1068854) | about 7 months ago | (#44923787)

Does this explain how Spider-Man can shoot and then swing on webs that are attached to... what? Clouds? The International Space Station?

Re:Yes, But... (4, Informative)

deusmetallum (1607059) | about 7 months ago | (#44923825)

He lives in New York, he's always swung from the multitude of high rises.

Re:Yes, But... (3, Interesting)

The Grim Reefer (1162755) | about 7 months ago | (#44923963)

He lives in New York, he's always swung from the multitude of high rises.

I'm guessing you're a little younger than I am, because I still remember the original 1960's Spider-man cartoon. He managed to swing across the Hudson River frequently. I recall one episode where he managed to "swing" to Mexico, or Central America even. Even so, not every area in all five boroughs of NY are covered in skyscrapers you know. He lived in a single family house with his aunt.

Re:Yes, But... (4, Funny)

meerling (1487879) | about 7 months ago | (#44924283)

You're trying to work out continuity issues from an old and poorly made no budget ancient cartoon?
You might as well complain that dropping an anvil on sombody's head will not result in a bump but will crush their freaking skull and kill them.
Besides, Spiderman doesn't do web flight. He must not have been bit by a gossamer spider. :)

Re:Yes, But... (1)

CanHasDIY (1672858) | about 7 months ago | (#44924549)

You might as well complain that dropping an anvil on sombody's head will not result in a bump but will crush their freaking skull and kill them.

Yea, WTF is up with that???

Re:Yes, But... (0)

ciderbrew (1860166) | about 7 months ago | (#44923847)

It doesn't explain why another film that added nothing was made so soon after the last batch. The amination was slightly better only looking like Woody getting cross with Buzz screaming "You, Are, A, Toyyyyy!" in half the cgi shots.

Re:Yes, But... (3, Funny)

camperdave (969942) | about 7 months ago | (#44923857)

Sigh! Spiderman's webs attach to skyscrapers, streetlights, bridges and the like. That's why you never see him swinging around in the suburbs. Spiderman only fights crimes downtown.

batman (0)

schneidafunk (795759) | about 7 months ago | (#44923891)

Similar to why batman only fights crime at night; How can he see the bat signal in the sky?

Re:batman (5, Informative)

MickyTheIdiot (1032226) | about 7 months ago | (#44923935)

The bat signal itself doesn't fit with physics.

My parents have owned a searchlight rental business for 30 years now. For the first Batman movie they were asked to put a bat signal cutout on the searchlight to simulate the bat signal. The thing is that searchlights have too high a candlepower and the light just bends around the cutout. The light spreads more the farther away from the searchlight. It looks cool when shown against a wall, but far out in the sky it simply doesn't work. The physics of light doesn't allow it.

Re:batman (1)

ArcadeMan (2766669) | about 7 months ago | (#44924027)

What about "lasers"? /Dr.Evil

Re:batman (0)

Anonymous Coward | about 7 months ago | (#44924615)

Lasers pointed into the sky willy-nilly. What a wise idea. I'm sure there is no chance of anything going wrong there.

Re:batman (1)

rubycodez (864176) | about 7 months ago | (#44924067)

you'd need a lens, the cost would be immense

Re:batman (1)

CanHasDIY (1672858) | about 7 months ago | (#44924561)

you'd need a lens, the cost would be immense

Not for billionaire playboy Bruce Wayne.

Re:batman (1)

MickyTheIdiot (1032226) | about 7 months ago | (#44924579)

Nevertheless, if you watch the first Batmovie when the Batsignal is introduced it is shown with a genuine searchlight with a cardboard cutout.

It's just a movie... :P

Re:batman (1)

SuricouRaven (1897204) | about 7 months ago | (#44924609)

What about using a much larger cutout, much further from the light? They don't have to be attached unless you need to point it.

Re:batman (0)

Anonymous Coward | about 7 months ago | (#44924721)

Nolan's movies just beat you, they count right? =p

http://www.youtube.com/watch?v=DImh0ac-jdQ

Next step is testing (5, Insightful)

schneidafunk (795759) | about 7 months ago | (#44923823)

"Of course, Gorham’s ideas will need to be tested by actually measuring the charge on gossamer spider silk as it is generated. That’s an experiment for an enterprising biologist to take on."

Nature is amazing (4, Insightful)

brunes69 (86786) | about 7 months ago | (#44923873)

To me stuff like this is what proves evolution. There is no one in their right mind who could sit there and convince me that such an obtuse solution to move from point A to point B is "by design", vs. random evolution.

Re:Nature is amazing (4, Insightful)

jones_supa (887896) | about 7 months ago | (#44923931)

I sometimes tend to think the opposite: some of the evolution's achievements seem so precisely engineered that it feels more like a designer's product than test of time. Not that I would actually believe in intelligent design and all that stuff.

Re:Nature is amazing (5, Insightful)

MadKeithV (102058) | about 7 months ago | (#44923957)

I sometimes tend to think the opposite: some of the evolution's achievements seem so precisely engineered that it feels more like a designer's product than test of time. Not that I would actually believe in intelligent design and all that stuff.

Most "precisely engineered" stuff that's actually engineered is still the product of large quantities of trial and error, at some level :)

Re:Nature is amazing (1)

The Grim Reefer (1162755) | about 7 months ago | (#44923993)

To me stuff like this is what proves evolution. There is no one in their right mind who could sit there and convince me that such an obtuse solution to move from point A to point B is "by design", vs. random evolution.

I fail to see how this is an "obtuse solution". I find it very elegant.

Re:Nature is amazing (1)

brunes69 (86786) | about 7 months ago | (#44924097)

It's obtuse because instead of giving this insect wings, it does this.

Re:Nature is amazing (2)

meerling (1487879) | about 7 months ago | (#44924307)

Spiders are arachnids, not insects. Scorpions are their relatives, not flies. Arachnids don't have wings, but they found a novel use for something they did have, that's a hallmark of evolution.

Re:Nature is amazing (3, Interesting)

brunes69 (86786) | about 7 months ago | (#44924493)

You are missing the point and arguing my own point.

IE if Intelligent Design was real, then this "designer" would have given arachnids that had to fly wings, and what you think of as an arachnid would be different.

He wouldn't have made them make these strange parachutes because it is not as efficient. This is something evolution did to solve the problem of "I don't have wings how do I move around". If the designer was intelligent it wouldn't be a problem in the first place.

Re:Nature is amazing (5, Insightful)

RKThoadan (89437) | about 7 months ago | (#44924699)

"not as efficient?" These seem a whole lot more efficient than wings to me. A single one-time expenditure of energy and they go for miles. There are downsides to this method of course, most obviously that they don't have any control of where they go. But if you accept that limitation this seems to be a nearly optimal method of flight.

Re:Nature is amazing (1)

Bucc5062 (856482) | about 7 months ago | (#44924727)

I feel that is a judgement call. Who is to say wings would be more efficient? With the spider's method the energy output is in just creating the thread, whilst wings would require much more energy output on a continuous basis. Like comparing a balloon to a fixed wing airplane. Both move you from point A to point B, but one does so with a lot less energy involved. Seems like a pretty good solution for the spider.

Re:Nature is amazing (0)

Anonymous Coward | about 7 months ago | (#44924747)

Supposing ID is real, why couldn't "the designer" have just done this in the first place thus never presenting a problem. Why do you think it would have had to have been an afterthought of "the designer?" I don't really understand where you're going with this.
 
BTW, you're looking at evolution wrong. Evolution doesn't "do" anything let alone solve problems. This isn't a video game where you get some kind of ability for making it to the next level. Evolution isn't a conscious entity that decides to create a mutation based on some kind of perceived need of a life form. Mutations exist, more or less, as a random chance. If those mutations make it easier to a species to survive it will likely get handed down through future generations until the mutation is the norm. You and I have some level of mutation. If we were still cavemen running across grasslands trying to catch tonight's dinner our mutations may or may not help decide if the hunt is successful. If it does then we'd breed and the mutation would likely be handed down. If it made it harder we'd likely die from lack of food and thus we'd not breed or our offspring would starve like we would and the mutation would come to an end.
 
This really isn't a hard concept.

not an effective strategy, seems bugs can't read (3, Insightful)

Thud457 (234763) | about 7 months ago | (#44924559)

The rule in my house is that if you have more than four limbs, you are a bug , and you belong outdoors. This policy is clearly stated on the signs underneath each door.

Honestly it looks more to me like... (2, Insightful)

Anonymous Coward | about 7 months ago | (#44924621)

Life imitates glitching :)

I mean this sounds exactly like some games that have double-jump and other glitches. Officially nothing is supposed to float unless it's lighter than air, but in reality there's about six (known) ways to exploit aspects of the world that were 'never intended' to end up with flight. Much like with videogame physics some animal figures out a trick, then keeps iterating until that trick is an art, then a science, and finally a way of life :)

Re:Nature is amazing (1)

rubycodez (864176) | about 7 months ago | (#44924163)

you're not thinking of all the dead spiders that ran into misfortune using this technique. it's great for the species, but a crap shoot for any individual spider. Just like fact that half of all birds on the planet die each year. flocks and migration good for species but not for individual bird

Re:Nature is amazing (1)

The Grim Reefer (1162755) | about 7 months ago | (#44924331)

you're not thinking of all the dead spiders that ran into misfortune using this technique. it's great for the species, but a crap shoot for any individual spider. Just like fact that half of all birds on the planet die each year. flocks and migration good for species but not for individual bird

You're correct, I'm not think about that. I think it's amazing that they are reaching heights of 13,000 feet with no wings at all.

Re:Nature is amazing (0)

Anonymous Coward | about 7 months ago | (#44924125)

Note to intelligent design advocates, and to many supposedly more "scientifically-minded" people: evolution is not "proven" or "disproven" by whatever subjective ideas one has about elegance.

Re:Nature is amazing (1)

meerling (1487879) | about 7 months ago | (#44924341)

Evolution is 'proven' to the same level as gravity. Yes, they are still arguing about the exact formula and still haven't been able to combine it with quantum physics either. Nothing in science is considered at 100%, just an increasing number of 9s after the decimal point. (Sometimes referred to as Sigmas. This includes our own existence.

Re:Nature is amazing (5, Insightful)

hort_wort (1401963) | about 7 months ago | (#44924245)

What if the intelligent designer just wanted to use evolution? I've never understood why the two solutions have to be exclusive.

Re:Nature is amazing (1)

brunes69 (86786) | about 7 months ago | (#44924445)

Then he isn't very intelligent, is he?

That is like saying "why would you use math to figure out the area of that rectangle when you can just guess randomly until you find a fitting number". Both solutions work but one is intelligent.

Re:Nature is amazing (2)

hort_wort (1401963) | about 7 months ago | (#44924781)

That is like saying "why would you use math to figure out the area of that rectangle when you can just guess randomly until you find a fitting number". Both solutions work but one is intelligent.

Scientists use the Monte Carlo method all the time. Depends on the experiment.

Re:Nature is amazing (0)

Anonymous Coward | about 7 months ago | (#44924851)

Thank you for your deep insights into the mind of God, if there is a God. You must fancy yourself a very intelligent person because you have an idea of how the universe should work and if anyone or anything other than yourself sees it another way then it's not intelligent.
 
If there is a God would you consider it a possibility that He/She/It designed it to be full of wonder and chance? That people can decide to embrace creation as their own little miracle or reject it for a life of dullness and misery?
 
There likely isn't a God but you're making some pretty heavy handed statements on his behalf. I wonder what you would think of yourself if it was found that there is indeed a God and you've been wrong in every assumption about that God that you've ever thought.

Re:Nature is amazing (1)

mrt_2394871 (1174545) | about 7 months ago | (#44924491)

What if the intelligent designer just wanted to use evolution? I've never understood why the two solutions have to be exclusive.

Well, Intelligent she might be (gives you the afternoon off, after all), but it's a bit more dispassionate than I'd want my Benevolent Omniscient Being to be. Have you read about all those parasites? The ones that eat their host from the inside out, the ones that affect the brain, so the host goes wandering out into wide open places and gets eaten, etc.

It's almost Lovecraftian.

Re:Nature is amazing (2)

SuricouRaven (1897204) | about 7 months ago | (#44924641)

Because 'intelligent design' was never a real theory. It was a legal dodge. An attempt to say 'God poofed everything into existence' without actually sounding religious.

Re:Nature is amazing (0)

Anonymous Coward | about 7 months ago | (#44924397)

There is no one in their right mind who could sit there and convince me that such an obtuse solution to move from point A to point B is "by design", vs. random evolution.

Wow! I never thought there were people in Slashdot that had never had any contact with an IT project of any kind!

Re:Nature is amazing (3, Insightful)

tobiasly (524456) | about 7 months ago | (#44924411)

To me stuff like this is what proves evolution. There is no one in their right mind who could sit there and convince me that such an obtuse solution to move from point A to point B is "by design", vs. random evolution.

As a scientist who happens to also believe in a creator, I don't understand why evolution and intelligent design have to be mutually exclusive. Why can't a creator have designed evolution?

The fact that life on this planet has undergone -- and continues to undergo -- evolution is undeniable. That doesn't prove that God doesn't exist. A system that is not only capable of propagating itself indefinitely but also continually updates itself over centuries and millennia.. now that's a pretty impressive hack if you ask me.

A common refrain from those who want to disprove intelligent design is "this creature's adapted behavior isn't the most efficient way to accomplish this task, so therefore it was not designed by an all-knowing, all-powerful creator". Just because this spider's means of locomotion is an "obtuse solution" also doesn't mean it's not "by design".

Who says God doesn't have a bit of Rube Goldberg in him? You're presuming that he's trying to create the perfect organism and he just can't quite get it right. Maybe he realizes that if he created the perfect spider it'll freak the hell out of his humans who will then wipe it off the planet.

Re:Nature is amazing (2)

brunes69 (86786) | about 7 months ago | (#44924565)

You're now trying to twist things around to fit into your concept of a creator.

Saying there is an intelligent designer who uses evolution makes no sense, because the whole point of evolution is that it is random. As such, it's actually very inefficient.

As I posted in another thread... this is like saying "why would you use math to figure out the amount of weight this can hold, when you can just guess randomly until you find a really big amount that it can hold". Both solutions work but one is intelligent and finds the OPTIMAL solution, and one is based on randomness over time fining A SOLUTION that works, but is rarely if ever optimal.

So, if you want to sit there and still believe in a creator who is so dumb that they use evolution, then fine... but I don't see why anyone would want to believe that.

African or European spider? (0)

Anonymous Coward | about 7 months ago | (#44923897)

What? I don't know that!! aaaaaaggghhhhhh

Spiderman paradox resolved. (0)

Anonymous Coward | about 7 months ago | (#44923903)

Peter parker doesn't attach his webbing to buildings. He simply launches it up and glides away.

hmm (1)

Anonymous Coward | about 7 months ago | (#44923915)

So if a human being is about 7,000,000 times heavier than a spider, would a scaled up thread charged at -0.21 coulombs allow us to fly?

Re:hmm (1)

DeathToBill (601486) | about 7 months ago | (#44924033)

Exactly what I'm thinking. Also, 120V per metre? Really? So the potential difference between my head and my feet is roughly the same as a wall socket? Okay, one is DC and the other is AC, but still, this should mean that if I put a meter into DC voltage mode and hold one probe up and the other down I should measure hundreds of volts, right?

Re:hmm (0)

Anonymous Coward | about 7 months ago | (#44924145)

1 meter = 3.2808399 feet You are a very short person unless you live in places that have 220 or 240V.

Re: hmm (1)

smaddox (928261) | about 7 months ago | (#44924247)

Agreed. That strong of a field seems unlikely to exist at all times. He may have based his estimate on the field strength prior to a lightning strike, which is on the order of a megavolt (10^6 V). Over a distance of 10 km (10^4 m), the approximate distance from ground to clouds, that works out to ~100 V/m. However, such large fields are not always present.

Re:hmm (1)

AlecC (512609) | about 7 months ago | (#44924467)

No. There is very little power behind that voltage, so your conductive body shorts it out. Effectively the field lines detour round your body - and hills, buildings etc. This has been used to make model aircraft avoid obstacles. Keep the voltage between wingtips zero.: as you approach a hill, the field lines lift, banking the aircraft and steering it away from the hill.

For this to work, the web silk would have to be a pretty effective insulator, which I believe is the case.

Re:hmm (1)

Baloroth (2370816) | about 7 months ago | (#44924487)

Yep, 120 Volts/metre. However, the air has a resistance of ~1.6*10^16 Ohms/metre as well, which means you aren't going to get a current and will therefore measure no voltage difference with a meter (for similar reasons it's also impractical for producing electricity). It's theoretically one way to produce levitation, but engineering wise thats quite difficult to actually do (for heavy objects).

Re:hmm (0)

Anonymous Coward | about 7 months ago | (#44924595)

Just as an experiment, try connecting your meter to a good earth ground and put a six foot long dielectric (insulator) into the air, connected only to the meter probe. It'll work better on dry, windy days.

I'm going to estimate you can pull a working voltage in the low two digits that way, if you don't mind it being sporadic with dangerous spikes into the thousands. Keep in mind that during storms, you can see thousands of volts at the tops of trees in the form of St. Elmo's Fire.

Re:hmm (0)

Anonymous Coward | about 7 months ago | (#44924679)

Yes, but the charge collected by the probes needs to be large enough to allow the approx. 100uA of current to flow in the 1Meg meter impedance (at 100V). So I guess you need pretty large area probes or alternatively use a very high impedance volt meter.

Re:hmm (1)

AlecC (512609) | about 7 months ago | (#44924443)

As I have read, yes. Somewhere about spiders suggested that a hair fifty miles long, given an atmosphere 50 miles deep, and a follicle much stronger than that actually fitted, could support a human, You might have to scale up the charge/m as well, but the physics still works.

120V/m - why can't we tap that (1)

RichMan (8097) | about 7 months ago | (#44923941)

So why are we unable to tap the planets electric field? Can someone explain this a little more. Seems like that is a power source just waiting to be tapped. Unintented consequences like collapsing earths magnetic sphere aside.

Re:120V/m - why can't we tap that (1)

ciderbrew (1860166) | about 7 months ago | (#44924019)

I've just read that one bolt of lightning powers one household with all their energy needs for a month. I'm not too sure how accurate that is; but I think we'll need a lot more than that.

Re:120V/m - why can't we tap that (1)

GameboyRMH (1153867) | about 7 months ago | (#44924057)

It might be worth setting up lightning rod power stations if there were a way to store it.

Re:120V/m - why can't we tap that (1)

ColdWetDog (752185) | about 7 months ago | (#44924293)

It might be worth setting up lots of $PowerStorageStations if there were ways to do that.

If we had a reliable, scalable, generally applicable (ort two out of three) method of storing instantaneous power generation from a variety of natural or man made resources, wind and solar power would completely stomp fossil fuels for baseline power use.

We don't and it doesn't. Yet.

Re:120V/m - why can't we tap that (0)

Anonymous Coward | about 7 months ago | (#44924475)

So a household uses 1.21 gigawatts of electricity in a month?

Re:120V/m - why can't we tap that (2)

n7ytd (230708) | about 7 months ago | (#44924693)

One household for a month, or one trip anytime into the past or future with your hovering time machine!

Re:120V/m - why can't we tap that (0)

Anonymous Coward | about 7 months ago | (#44924065)

Bring Wardenclyffe back online?

Re:120V/m - why can't we tap that (0)

Anonymous Coward | about 7 months ago | (#44924101)

It's a fine source of voltage, but the density is so low that it's not a good source of power.

Re:120V/m - why can't we tap that (0)

Anonymous Coward | about 7 months ago | (#44924103)

Its 120V at an infinitesimally small amperage.

Re:120V/m - why can't we tap that (3, Informative)

necro81 (917438) | about 7 months ago | (#44924135)

The earth's magnetic field is almost certainly unrelated. The magnetic field is generated internally due to us having a molten iron core. This atmospheric electrical field comes from the bulk transport, separation, and friction of huge air masses - like the kind that give rise to thunderstorms. There's interplay between the two, especially during a solar storm (e.g., aurorae), but you couldn't freeze the magnetic field by tapping the atmosphere.

As for why we can't tap that, I could only speculate. 120 V/m sounds like a sizable field - strong enough that we ought to be able to feel it. On the other hand, the E-field in an ordinary capacitor is many orders of magnitude greater (10s of volts, perhaps, but separated by just microns). You can get a greater E-field from peeling scotch tape off its roll.

Also bear in mind that an electric field, by itself, is not a store of energy. In order to make use of that field, you need to have charge traverse that field - a flow of electrons. If we think of the atmosphere between stratosphere and ground like a giant capacitor, its stored energy is 1/2 * C * V^2. The V term might be very large (120 kV/km, squared!), but if the C is tiny, then you end up without much energy. And do not conflate power and energy: you can get quite a spark from a discharging capacitor (or a lightning bolt!) - great instantaneous power - but it doesn't last. Unless there's some source to continuously replenish the charge separation, you may not be able to tap much energy. I suspect that the available energy is very diffuse; more diffuse than, say, the kinetic energy of wind that we are able to capture with turbines. You would probably need kilometer-sized antenna arrays to capture much useful power.

Lifters/Ioncraft propulsion mechanism? (0)

Anonymous Coward | about 7 months ago | (#44924041)

Looks like there may be much more to it than just Ion Wind [wikipedia.org]

Aerospace engineers should definitely investigate it.

anonymosside (0)

Anonymous Coward | about 7 months ago | (#44924359)

"Ballooning" Spiders Use Electrostatic Forces To Generate Generosity on PCBs.

Uh Oh (1)

b4upoo (166390) | about 7 months ago | (#44924611)

NSA and DOD will have a nervous breakdown trying to build a drone the size of a small spider that can make silk.

Tesla's Flying Machine (0)

CanHasDIY (1672858) | about 7 months ago | (#44924689)

I think this is the basis upon which Nikola Tesla based the engines for his never-completed flying machine: [peswiki.com]

“When I found that I had been anticipated as to the flying machine, by men working in a different field, I began to study the problem from other angles, to regard it as a mechanical rather than an electrical problem. I felt certain there must be some means of obtaining power that was better than any now in use. And by vigorous use of my gray matter for a number of years, I grasped the possibilities of the principle of the viscosity and adhesion of fluids and conceived the mechanism of my engine. Now that I have it, my next step will be the perfect flying machine."

"An aeroplane driven by your engine?" I asked.

"Not at all," said Dr. Tesla. "The aeroplane is fatally defective. It is merely a toy — a sporting play-thing. It can never become commercially practical. It has fatal defects. One is the fact that when it encounters a downward current of air it is helpless. The "hole in the air" of which aviators speak is simply a downward current, and unless the aeroplane is high enough above the earth to move laterally it can do nothing but fall."

"There is no way of detecting these downward currents, no way of avoiding them, and therefore the aeroplane must always be subject to chance and its operator to the risk of fatal accident. Sportsmen will always take these chances, but as a business proposition the risk is too great."

"The flying machine of the future—my flying machine—will be heavier than air, but it will not be an aeroplane. It will have no wings. It will be substantial, solid, stable. You cannot have a stable airplane. The gyroscope can never be successfully applied to the airplane, for it would give a stability that would result in the machine being torn to pieces by the wind, just as the unprotected aeroplane on the ground is torn to pieces by a high wind."

"My flying machine will have neither wings nor propellers. You might see it on the ground and you would never guess that it was a flying machine. Yet it will be able to move at will through the air in any direction with perfect safety, higher speeds than have yet been reached, regardless of weather and oblivious of “holes in the air? or downward currents. It will ascend in such currents if desired. It can remain absolutely stationary in the air, even in a wind, for great length of time. Its lifting power will not depend upon any such delicate devices as the bird has to employ, but upon positive mechanical action."

“You will get stability through gyroscopes?" I asked.

“Through gyroscopic action of my engine, assisted by some devices I am not yet prepared to talk about," he replied.

Re:Tesla's Flying Machine (1)

kamapuaa (555446) | about 7 months ago | (#44924827)

Tesla was a mysticist quack by the end of his life, endlessly promising inventions that he didn't have designs for and must seem impossible. He was a great scientist and experimenter in his early career, sure. He was a quack by the end.

Re:Tesla's Flying Machine (1)

CanHasDIY (1672858) | about 7 months ago | (#44925049)

Tesla was a mysticist quack by the end of his life, endlessly promising inventions that he didn't have designs for and must seem impossible. He was a great scientist and experimenter in his early career, sure. He was a quack by the end.

OK... the interview quoted, if you bothered to check the link, was given in 1911, long before his so-called slide into madness.

For the record, one of the things Tesla spoke about that gave people back then cause to question his sanity was his theories about a method of sending video and audio signals through the air - technologies that we take for granted today.

So, probably less 'quack' and more 'a solid generation before his time.' But by all means, don't let that diminish your sense of mental superiority over the man who invented more stuff you use every day than I could list in a Slashdot post.

Spider Silk powered flying car... (1)

Macdude (23507) | about 7 months ago | (#44925005)

So how long until I can use this technology to finally get my flaying car?

Spider Silk powered flying car... (1)

Macdude (23507) | about 7 months ago | (#44925039)

So how long until this technology can be used to build the flying car I've been promised for several decades?

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