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Researchers Unravel Mystery of Lightning Diversity

Posted by ScuttleMonkey on Mon Mar 31, 2008 12:24 PM
from the shocking-research dept.
Science Technology
coondoggie writes to tell us that researchers from Penn State and New Mexico Tech have unraveled the mystery of lightning diversity. A new "Lightning Mapping Array" has been able to show detailed models on how lightning acts. "About 90% of lightning occurs inside clouds and is not visible to the casual observer, researchers said. The researchers wondered if lightning that appears within clouds and the lightning that escapes upward or downward shared the same development mechanisms, researchers said. Lightning forms in clouds when different areas of the cloud become either positively or negatively charged. Once the electric field near a charged area exceeds a certain propagation level, lightning occurs. The type of lightning depends on where the charge builds and where the imbalance in charge exists in the clouds. The mechanism behind different types of lightning is what the new model shows, researchers said."
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[+] New NASA System to Keep Lightning Off The Launchpad 31 comments
coondoggie writes to tell us that NASA is building a new system to protect people and equipment on the shuttle launchpad from lightning strikes. "The new structure called a catenary wire system, will be the largest on the space compound and will feature large cables strung between three 594-foot-tall steel and fiberglass towers. Each tower is topped with a fiberglass mast and a series of catenary wires and down conductors designed to divert lightning away from the rocket and service structure. This configuration helps keep the vehicle isolated from dangerous lightning currents, NASA said."
Submission: Researchers unravel mystery of lightning diversity by coondoggie (973519)
[+] Laser Triggers Electrical Activity In Thunderstorm 167 comments
esocid writes "A team of European scientists has deliberately triggered electrical activity in thunderclouds for the first time by aiming high-power pulses of laser light into a thunderstorm. At the top of South Baldy Peak in New Mexico during two passing thunderstorms, the researchers used laser pulses to create plasma filaments that could conduct electricity. No air-to-ground lightning was triggered because the filaments were too short-lived, but the laser pulses generated discharges in the thunderclouds themselves up to several meters long. Triggering lightning strikes is an important tool for basic and applied research because it enables researchers to study the mechanisms underlying lightning strikes. Moreover, triggered lightning strikes will allow engineers to evaluate and test the lightning-sensitivity of airplanes and critical infrastructure such as power lines. Research into laser-triggered lightning has been going on for some years. Until now, no experiment was able to produce a long enough plasma channel to affect the electrical activity inside clouds."
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  • Ball Lightening (Score:5, Interesting)

    by eldavojohn (898314) * <my/.username@@@gmail.com> on Monday March 31 2008, @12:28PM (#22922924) Homepage Journal
    I'm shocked there's no mention here of ball lightening [wikipedia.org] and I wonder if they can time the discharge of 60 MHz RF radiation from each lightening strike. If they can, I would be interested in seeing the outliers that last longer than a fraction of a second. Ball lightening is often reported to last several seconds and I think this would be easy to spot if they wanted to try to verify that it actually occurs in nature.
    • Ballroom Blitz goes at about 120 bpm, but I have not heard it in nature. Maybe it is different there.

    • Presumably because... (Score:4, Informative)

      by Moraelin (679338) on Monday March 31 2008, @12:59PM (#22923236) Journal
      Presumably because noone knows wtf ball lightning even is. The hypothesised explanations include such stuff as it being essentially a ball of burning silica, and a few other things which aren't even, strictly speaking, lightning. As in, an electrical discharge.

      So basically we don't _have_ a model for that one at all, and that's a bit mandatory for a simulation.

      To make things worse, ball lightning is (compared to regular one) a very rare and unpredictable phenomenon. You can pretty much rely on the next thunderstorm to provide you with a bunch of regular lightning to study. (Fly your kite in it, like Franklin, for example.) Ball lightning is harder to track down and study. You don't know when or where it will happen.
      • Rare indeed, I saw ball lightning when I was about 13. I have never seen it again since (I am now 45+) and it was a memorable sight and have hoped to see it again. It lasted 3-5 seconds as it rolled down my neighbor's roof, danced along the rain gutter, then exploded in to a bright turquoise flash and was gone. It did make a sizzling/crackling and zzzzt sounds.
    • Stop wearing 100% cotton pants?
    • bzzt

      An unacknowledged pun - normally the slashdot wouldn't put up with such a thing.
    • If I remember correctly, the array uses time-domain binning of RF "pulses" from the lightning along with a big-damn matrix inversion to generate their data. The reliance on pulses means you can't look for signals of a specific frequency. I'm also curious as to where this 60 MHz signal is supposed to come from. Most lightning acts as a very, very wideband (RF through X-rays) signal source.

    • You mean Ball Lightning? (Score:5, Funny)

      by Kohath (38547) on Monday March 31 2008, @01:40PM (#22923574)
      Ball Lightning is the most painful kind of lightning.

      On the other hand, "ball lightening" is yet another failed spin-off product of the tooth-whitening industry.

    • Ball lightning (note spelling) is still not understood. Every now and then someone trots out a new theory which explain some features but not all. Theories range from propagating vortices of chemical reactions to cool plasma to plasma generated by rf from storms in standing waves etc etc.

      This is about other lightning. I was most interested in the 'blue lightning', that is the "bolt from the blue" -- lightning bolts in blue sky way ahead of the storm front. I have seen it and it is pretty creepy, you sudden

    • Well damn, and here I was going to post about how amazed I was that the submitter and Taco spelt "lightning" correctly.

      You suck.

  • On-topic golf joke (believe it or not) (Score:4, Funny)

    by sm62704 (957197) on Monday March 31 2008, @12:31PM (#22922942) Journal
    Two guys are playing golf when rain threatens. One of them says to the other "we better stop, a thunderstorm is coming up and it could be dangerous."

    "Relax" says the second one, and pulls a club from his bag and holds it high in the air.

    "WTF are you doing!?!?" exclaims the fist golfer.

    The second replies "Not even God can hit a one iron!"

  • Charging Mechanism? (Score:1)

    by Anonymous Coward
    How do they become charged?

    • Re:Charging Mechanism? (Score:5, Informative)

      by mikael (484) on Monday March 31 2008, @12:50PM (#22923148)
      Water molecules evaporating from the trees, vegetation, lakes and oceans carry an ionic charge up to the clouds with them. Turbulence within the clouds also help charge build up.

      • Re: (Score:2, Interesting)

        by Mathinker (909784)
        > Water molecules evaporating from the trees, vegetation, lakes and oceans carry an ionic charge up to the clouds with them.

        What kind of ionic charge (positive or negative)? What is the mechanism involved?

        > Turbulence within the clouds also help charge build up.

        How?

        Your turbulence explanation sounds like the "when clouds collide they rub against each other and generate massive static electricity" explanation-for-children I remember from (old) books of my tender youth.

        How clouds accumulate the charge s

    • Re:Charging Mechanism? (Score:5, Funny)

      by Kohath (38547) on Monday March 31 2008, @01:47PM (#22923644)
      In even the darkest clouds, electricity can be conducted through the silver lining. When the charge builds up enough, it strikes the earth, often near large quantities of metal. This is the #1 cause of death for leprechauns. Leprechauns that survive enough of these storms are considered lucky.

      On another topic, why won't Wikipedia accept my submissions?
  • I can no more criticize cloud lightning than I can criticize lightning in general. I can no more criticize those who fear lightning than I can disown my grandmother -- a woman who helped raise me, a woman who sacrificed again and again for me, a woman who loves me as much as she loves anything in this world, but a woman who once confessed her fear of lightning which flashed in the night, and who on more than one occasion has uttered lightning stereotypes that made me cringe.

    Lightning does not define me. It provides context, but it does not provide the content.
    • Offtopic? Yes, but HILARIOUSLY offtopic. Come on, this is great absurdist humor. BadAnalogyGuy is like Garrison Keillor and Robin Williams crack addicted love-child.

  • I got hit by lightning in 1998 (Score:4, Interesting)

    by Anonymous Coward on Monday March 31 2008, @12:34PM (#22922994)
    It hurt.

  • Teach the controversy (Score:5, Funny)

    by UbuntuDupe (970646) * on Monday March 31 2008, @12:40PM (#22923052) Journal
    This theory is all well and good, but shouldn't students also be exposed to alternate explanations, such as those involving the thunder god, Thor?

  • I Worked On This Project (Score:5, Insightful)

    by Stranger4U (153613) on Monday March 31 2008, @12:41PM (#22923062)
    New array? I worked on this project in 99-00 and it was several years old then. I think "new" here just corresponds to awareness in the minds of the public. Papers derived from this research have been around ten years, at least. The results are, however, quite impressive. It's possible to plot, in time, the path a lightning bolt takes through a cloud. Airplanes are also quite easy to spot on their graphs. A quick look on their research page might make for interesting reading: Langmuir Labs [nmt.edu].

  • Power Source? (Score:4, Interesting)

    by JohnSearle (923936) on Monday March 31 2008, @12:48PM (#22923136)
    I'm curious as to when they're going to be able to harness this energy as an alternative power source. It would be very cool to see blimps as power stations siphoning off energy from the clouds. I assume this isn't feasible (yet at least), considering I haven't heard anything about it...

    Can any explain the major defects this type of energy gathering?

    - John

    • Can any explain the major defects this type of energy gathering?

      • Huge gas filled bags of air, hostage to the air currents, in an air mass full of turbulence?
      • Huge gas filled bags of air, sent to collect the massive discharges of energy called lighting by us mere mortals.?
      • Discharges so strong that they instantly superheat the air around them and cause a thundering boom from the shockwave of the expansion caused?

      No, I can't think of any reason why no one has done that before. Dr. Frankenstein.

      • Re: (Score:2, Interesting)

        by JohnSearle (923936)
        I didn't specify that it be a necessity that it depend on blimps, it could very well be ground based... According to Wikipedia [wikipedia.org] the CN Tower gets struck 40-50 times per year by lightening. I would figure it would be possible to greatly increase that number if you tried.

        I'm sure you understood the point of my question, which was: why hasn't the clouds been harnessed as a source of energy? No need for belittlement.

        - John

        • Re:Power Source? (Score:4, Insightful)

          by Kandenshi (832555) on Monday March 31 2008, @01:25PM (#22923450)
          I'm not an electrical engineer, but...
          What the hell do you put that energy into? Some sort of massive capacitor that can be discharged gradually into the system? I'm not sure that those are able to absorb that much electricity that quickly at an even remotely reasonable price.
          Just directly funneling into the power grid seems like it'd cause all sorts of issues. Massive spike of energy that lasts a second or so? Sure it'll power quite a few homes, but it'd also melt quite a few lines I'd think.
          • Perhaps it's infeasible to take that power directly, but what about indirectly... such as using the energy discharges to superheat some form of matter that you would be able to control a little better (or anything similar). Is there no medium on which to harness this type of energy? And does anyone know of any research currently be done on this subject? I would be certainly interested in hearing about it...

            - John
    • There's a Helium shortage [usatoday.com].

      And, needless to say, the alternative is not safe.

      • Well how about ground based... Like I said in reply to the other guy, the CN Tower is considered to be the world largest lightening rod, and according to Wikipedia is struck over 40-50 times per year (which I'm guessing could probably be increased if the attempt was made).

        - John
    • I'm just basing this on information available on wikipedia, but....

      a lightning strike does not contain that much energy. Enough to power a 100W bulb for 2 months.
      It seems that the highest strike rates are on the order of 100 strikes/km^2 per year.
      Since the surface area of the earth is 5*10^8 km^2, we get at max 5*10^10 strikes per year, enough to power
      10 bulbs for each person on earth per year...
    • A quick search doesn't turn up much, but I remember reading years ago about an experimental power station in Australia that attempted to charge a huge battery bank using lightning rod(s). The biggest problem with their system was that after each strike, the generating equipment (and some of the batteries) got completely destroyed -- severely limiting the economics of such a system -- though it did (sort of) work. I've no idea if the experiment is still in operation. My guess is not, since I'd imagine it'
    • First off the total energy in a lightning bolt is relatively small. According to http://en.wikipedia.org/wiki/Lightning [wikipedia.org] it is only 500mJ on average which is equivelant to a 100 watt light bulb for 57.8 days. Given that a joule is equivelant to a watt second, this would mean that a typical larger coal plant can be around 1000MW of electrical output we are talking about a typical coal plant being equivelant to two continious lightning strikes. Of course, there are smaller power plants at the 50MW level,
    • Besides sporadic high intensity events that require expensive storage, the tendency of lightning to unpredictably destroy equipment, the wear and tear on using the equipment in wet weather and providing alternate grounding paths that will deplete the lightning before it can be gathered, and the low power density for deployed infrastructure required to gather the energy?

      I can't imagine a good reason it's not solving the world's power problems right now!
    • I'll want to add to the other problems (not that much energy available and the probable rapid wear of the equipments) that, if we do that on a large scale, we may all die from cancer because there is a theory that lightnings participate in the earth radiation shield (in particular the Van Hallen Belt).
  • Further research is indeed needed. For instance, the current postulate for Ball Lightening is still not verified, though some have infamously postulated its origins come from the Tea-Bag phenomenon.

  • Ball lightning not only occurs atmospherically (Score:5, Informative)

    by LM741N (258038) on Monday March 31 2008, @01:05PM (#22923292)
    It has been reproduced in submarine battery switches on demand, occasionally during shorts in electrical equipment, and of course in Tesla's big coil. He considered it a big nuisance. AFAIK, no one has ever duplicated Tesla's production of Ball Lightning.

    There are all sorts of theories. One is that plasma is held in place by the presence of RF radiation somehow induced by lightning. Another theory is that is chemically based upon NO2, so its not electrical at all- other than that the lightning produces the NO2.

    None of the theories currently address the eyewitness accounts of the balls going through walls, or just suddenly popping out of nowhere in peoples' houses.

    There is an entire book called "Ball Lightning: An Unsolved Problem in Atmospheric Physics" by Mark Stenhoff. Available from Amazon by special order or used copies are available. Its really pricey $160, so I would go for a used copy that is $40 or so.
  • Sounds like a big CRT screen. One part of the cloud acts as the electron gun and the other part the acceleration field. The ground would be the phosphor-coated screen.
  • Well, they could also spend some resources to try to extract energy from lightning.
    Along with wind power plants is also a nice method to extraxct energy from the athooshere, which seems not to be a bad idea.
    • No current materials are usable for this. It's far, far, FAR easier to just build better wind plants or solar panels. A MASSIVE capacitor array might be able to store the energy, but the expense and size would be prohibitive. Large energy storage is used in Sandia's Z machine, capable of outputting pulses of 2.7MJ. A planned upgrade would bring it up to 20-30 MJ. An average bolt of lightning has about 500MJ of energy. Positive lightning carries as much as 300GJ. The Sandia researchers hope to create a Z-pin
      • Try discharge a lightning bolt down a swiming pool with grounding. You get a log of oxygen and hydrogen at once by electrolysis!
        It could be cheap.

  • obDoc (Score:3, Funny)

    by Rob T Firefly (844560) on Monday March 31 2008, @01:47PM (#22923640) Homepage Journal
    That's nifty and all, but how do I get it into my damn flux capacitor?
  • Interesting article, but it didn't answer one question I've had for a while: what controls the color of lightning? I was recently in the Caribbean, and was dumbstruck to find out that lightning there was a beautiful shade of pink. Not blue, not white, but pink. I've since then seen multiple references to pink lightning, but no explanation for what is causing it. I've seen some theories around distance (atmosphere absorbs blue light more than red light) and particle content, but none of them seemed to apply
  • Ok, I was a bit miffed when the U of MI laser article was posted http://science.slashdot.org/article.pl?sid=08/02/17/0656203 [slashdot.org] and there was talk of it wiping out entire solar systems with the sheer power, but now am getting a similar feeling here with harvesting lightning for energy. I guess I must have unusual pet peeves...

    Physics 101 (skip if this is boring).

    Power != energy. Power is the rate of change of energy. Energy is the total needed to do something. This means that if you have a very

  • Lightning is cool, researchers said. It goes zappy zap all around, researchers said. Sometimes it goes up, and sometimes it goes down, researchers said. Occasionally, it goes sideways, which is cool, researchers said. They have a new tool with which to look into the cloud to see lightning, researchers said, but when it came to actually describing the cool tool, researchers didn't say.

    Also, researchers said other stuff, researchers said.

    Seriously, people... I know English is an elective when you're taking a

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