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Researchers Unravel Mystery of Lightning Diversity
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."
I'm shocked there's no mention here of ball lightening 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.
My work here is dung.
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!"
mcgrew's razor: Never attribute to stupidity that which can be explained by greedy self-interest
Ballroom Blitz goes at about 120 bpm, but I have not heard it in nature. Maybe it is different there.
How do they become charged?
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.
It hurt.
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?
Apology to Ubuntu forum.
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.
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
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.
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.
A polar bear is a cartesian bear after a coordinate transform.
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.
I wonder if "The researchers wondered if lightning that appears within clouds and the lightning that escapes upward or downward shared the same development mechanisms, researchers said." is a grammatically correct sentence, I say.
bzzt
An unacknowledged pun - normally the slashdot wouldn't put up with such a thing.
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.
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...
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.
Maybe Computers will never be as intelligent as Humans.
For sure they won't ever become so stupid. [VR-1988]
That's nifty and all, but how do I get it into my damn flux capacitor?
Slashdot Burying Stories About Slashdot Media Owned
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 to what I saw in the Caribbean: distances where well within what I was used to, and particle content, due to rain and lack of industry, should have been close to zero. Anyone have any ideas?
Those who can, do. Those who can't, sue.
I'm sure they have some weapon in their stockpile somewhere that generates lightning. We need a control group damnit!
"Quote me as saying I was mis-quoted." -Groucho Marx
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 small amount of energy, but use it fantastically fast, the power is very large. The U of MI laser and a lightning bolt are similar in that the energy is not all that large compared to the power they develop (relative to everyday objects) - due to thier acting over a very short time period. In reality a lignting bolt probably has a few orders of magnitude more energy than a U of MI laser discharge while the laser has an order or two more magnitude more power.
According to wikipedia http://en.wikipedia.org/wiki/Lightning a typical lightning bolt has only 500MJ of energy, or the amount to power a 100 watt bulb for 57.9 days. Given that a Joule can be thought of as a watt second, a typical larger coal plant can produce 1000MW of energy or the same as two average lighting strokes per second. Even smaller power plants weigh in at 10-50MW. It is not feasible to capture lightning even 0.0001% of the time, not to mention storing and converting the power efficently. Therefore it is impractical to even try because there really isn't that much energy to gather.
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 suddenly realise that nowhere is safe. Should be an interesting paper to read.
Bitter and proud of it.
sigfault (core dumped)
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 science degree, but for the love of our dear and fluffy lord, TAKE IT!!!
If I knew the wedgies I gave you back in 6th grade would have resulted in this . . . I might have taken a moments pause.