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Ball Lightning Created In the Lab
EWAdams writes to point us to a New Scientist report that the mysterious phenomenon of ball lighting has now been created in a Brazilian research lab. The phenomenon has long been reported anecdotally but never explained or understood. Scientists have devised numerous possible explanations, including mini black holes left over from the Big Bang, but have had little success in producing working examples. From the article: "A more down-to-earth theory... is that ball lightning forms when lightning strikes soil, turning any silica in the soil into pure silicon vapor. As the vapor cools, the silicon condenses into a floating aerosol bound into a ball by charges that gather on its surface, and it glows with the heat of silicon recombining with oxygen. To test this idea, a [Brazilian] team... took wafers of silicon just 350 micrometers thick, placed them between two electrodes and zapped them with currents of up to 140 amps. Then... they moved the electrodes slightly apart, creating an electrical arc that vaporised the silicon. The arc spat out glowing fragments of silicon but also, sometimes, luminous orbs the size of ping-pong balls that persisted for up to 8 seconds." Here is a movie of the phenomenon.
I think, it will fly if there's a significant potential difference between the ground and air, as it can be during a thunderstorm when the earth and clouds become like capacitor plates.
In this case a conducting plasma ball will move along the lines of resulting electric field, but because earth landscape is not flat, it will move in rather strange trajectories.
I find it fascinating that it displays almost no friction to the floor as it moves about. Plus, the gas jets tell of a very complex combination of structure and chemical process occurring.
It will be interesting to read more research on the subject when it becomes available.
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These things stay on ground... when I was a kid I once saw a ball of lightning and it danced along a barbed wire fence. This is a start but not the whole truth...
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...that isn't it. The most accurate description I can give based on the one time I witnessed it is that it looked very similar to the luminescent jellyfish that you might see when boating at night (soft glow, bluish, semi-translucent). That 'look', and the fact that what I saw seemed to 'float' (the video shows something that is most definitely not weightless as it drops and bounces about)leaves me unimpressed. I don't know what causes ball lighting (I'm sure it's rather anticlimactic whatever it is), but this isn't it. Just my two cents.
A couple of years ago I tested the fireplace in our just build new house. It is a fireplace which has a glass door to prevent smoke from entering the living room. Between the door and the frame there is a gap of two millimeter wide. I had put in tropical wood, leftovers of a bridge build in our neighborhood. I had set the lever to the extreme and lots of air (oxygen) was flowing in. Suddenly there was an impressive explosion and about a dozen of these pearls flowed through the fireplace. Three of them moved towards the glass door and actually seemed to move through the glass door near the edge of it. The glass door remained intact. I wrote some reports about it and have send them to some scientists working in this field. One of the possible explanations was that the balls might have been fast rotating strings, capable of moving through the gap. It was a wonderful experience which I have not been able to recreate. It very much looks like these balls in the video
Why do we suppose that all ball lightnings are generated the same way? This is a pretty strong statement as far as I can tell, without the appropriate grounds to make it. However, this particular theory definitely has a reason to live in my eyes, since it would explain generation of lightning balls at large altitude [Caucasus mountains, where they pose a threat to mountain climbers; at least one group has perished to a ball lightning-like object with only one injured survivor remaining], since silicates [particularly olivine] are abundant in Caucasian rock.
It very much looks like liquid metal balls bouncing on the floor, these are produced very often when using an electric arc welder.
This isn't ball lightning, what's happening here is mostly oxidation...
I remember as a kid, attaching some extra thin solder wire between a couple nails in a small piece of scrap wood attached to a power cord. Plug the cord into the outlet and the solder would explode in a shower of sparks. I'd do this on sheets of butcher paper, because the solder sparks would hit the paper, incandescent white, and bounce around just like the silicon in this demonstration (probably burning both the flux and some of the lead in the solder) leaving behind these intricate little trails all over the paper. At the end, you'd find these tiny little balls of solder (typically 0.4-0.8 mm.) Point is, you'd ionize a little metal, and get that metal (lead or silicon it doesn't matter) to oxidize, and there's clearly a ball of vaporized metal surrounding the burning bit at the middle, but this is not by any stretch anything like ball lightening.
It can bounce around, fly through the air, float serenely across the room... it has a very broad repertoire of movements. The behaviour in the video is within the range of reports, so you can't rule it out because of that. The visual appearance of the balls is consistent with the ball lightning I've seen personally, and reports vary widely so far as colour as well as behaviour.
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A friend of mine was swimming in a lake in the eighties and some ball lightening appeared. It bounced along the surface of the lake near him, scaring him and others on the lake beach somewhat as he raced to the shore.
It dissipated shortly after he got out, and he went straight to the lakeside bar to get a drink, touched the proffered glass, and it exploded. Other than that and a healthy dose of 'holy fuck', he had no ill effects.
This is no explaination for the phenomenon. Soil? Lasting 8 seconds?
I have a personal experience of ball lighting and it completely contradicts the results suggested.
I was 10 years old ( 32 years ago ) living in an urban town in Crawley, UK. There was a heavy thunderstorm - which I should point out would be a minor storm relative to other countries. It was about 9pm at night.
My brother and I had been in bed in our rooms when my mother came up to us and brought us downstairs. She saw visibly upset by something ( I still recall the event clearly now, for that reason ).
Her explaination was that she had been reading when she saw a ball of light, about the size of a grapefruit, arise slowly from the telephone. It hovered at about chest height for a while and hen slow drift towards the closed kitchen door. It dissipated when it came into contact with the door.
That description doesn't tie up with a bit of soil igniting and burning for a few seconds.
I don't believe there is anything mystical about this phenomenon but I don't buy this work as being an explaination for it.
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Yep - easiest way to make ball lightning - light a wide based candle, without any metal in it (no tea-lights!), place it in the microwave, in the middle of the plate. Nuke. Plasma ball appears, candle goes out, and plasma ball remains. Turn off microwave, the plasma stays a few seconds, before descending back into the candle.
I wouldn't be so quick to discount this as a major source of many instances of ball lightning. For starters, Silicon is the most common solid element on Earth, so there is plenty around. And I see no reason to think that Silicon would be the only element or molecule that could produce this effect. Also, the experimenters are also dealing with much less energy than a real lightning strike and much purer silicon than lightning would hit. Given higher energy (heat) and less silicon you might see something that would float more. This reminds me of something I saw years ago that wasn't quite ball lightning but had similarities. My wife and I were driving along some major power lines in Bloomington, IN, when lightning struck a transformer behind us (I saw it in the rear view mirror). A glowing, greenish ball streaked down one of the lines and passed our car leaving a long, thick trail behind. It was much like a cross between a phaser and photon torpedo effect in Star Trek... very cool. I'm not sure if there's much silicon in a transformer, but copper might explain the green color.
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it was, according to him, a very hot day, not a storm in sight. He didn't see where it came from, but he said it seemed to be moving towards him till he got out of the water.
Not being too conversant with electromagnetism I couldn't say whether this was because he represented an electrical 'hot spot' on the water or just that he was so freaked he thought it was following him.
It was, so far as he could tell, about a foot across.
There have ALWAYS been numerous theories, and numerous tests, which could explain a FEW of the properties of ball lightning, but never ALL of them.
A gas ball sounds good, except for numerous accounts of ball lightning traveling THROUGH solid objects (comming out the other side) all without causing ANY damage to the stationary object at all. How does burning silicon gas do that?
How does this burning gas ball slowly float inches away from people, and not cause them to feel the intense heat from the object?
And how does silicon gas (from a ground lightning strike) suddenly appear floating down the isle of a commercial aircraft in-flight?
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