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00:00Oh
00:30Oh, my God!
00:33Straight into me!
01:00I went for a walk on an August afternoon, blue sky over my head, just one distant thundercloud.
01:07I was with my dogs, and there was one peal of thunder, and I called my dogs to me because they're frightened of thunder.
01:15And I said, don't worry, you're all right as long as you're with me.
01:18And that's all I remember.
01:22I woke in a pool of blood.
01:24I didn't know what had happened to me.
01:25I thought I'd been shot in the back.
01:30I lay there for a long time, thinking I was going to die.
01:38I was in terrible pain.
01:40It was then that I realized I must have been hit by lightning.
01:43The storm came around and was just thundering all around me.
01:49And the only thing I could think of was that I swallowed fire.
01:53It's been a source of one of the features of the gods of every primitive religion in some modern religions.
02:11It's found all throughout art.
02:14It's something that people have always looked at and feared.
02:16Every lightning is different.
02:18It's something wonderful to look at.
02:19Every thunder is different.
02:20Overall, it's wonderful stuff.
02:24Lightning kills at least a thousand people every year.
02:28Each boat lasts a brief fraction of a second.
02:31It can be up to 30 miles long, and it's less than an inch thick.
02:35It's hotter than the surface of the sun.
02:37The air around the lightning channel is heated so violently that it explodes.
02:41You can hear the shockwave 15 miles away as a clap of thunder.
02:48The most common symbol in meteorology is a lightning discharge.
02:51It really is a dramatic event.
02:53It also represents one of the longest unsolved problems in classical physics.
02:58We still don't know fundamentally what causes lightning.
03:02It's still a meteorological mystery.
03:03For 250 years, we have known that lightning is an electrical phenomenon.
03:14But despite centuries of research, scientists are still struggling to understand exactly how
03:19such vast electrical forces are generated in a thundercloud.
03:23How a lightning bolt begins, or why it takes one path through the air, not another.
03:29Only now are we beginning to grapple with the intricacies of thunderstorms and lightning.
03:33And to realize the extent of lightning's effect across the entire planet.
03:44Severe thunderstorms occur mainly in a belt around the tropics and subtropics where the
03:48heat and humidity are high.
03:51At any one time, there are almost 2,000 individual active thunderstorms on Earth.
04:01One prime spot is Florida.
04:03Running across the centre of the state is Lightning Alley, a strip 60 miles wide with
04:08the highest incidence of lightning in the USA.
04:12People living here can expect to see lightning on more than 90 days a year.
04:15My one hole hinges on that cloud up there, and it looks pretty good.
04:25It's quarter till eight, the sun goes down about eight o'clock, so I can shoot about quarter
04:34after eight.
04:35That gives me a half hour, and that cloud right there just looks like it might do us some good.
04:38David Stillings lives in the middle of Lightning Alley.
04:51He calls himself the Lightning Stalker, and he hunts it with a camera.
04:57On July 1st of 1976, I captured my very first streak of lightning, and it's called Eruption,
05:09because it seemed like it was erupting right out of that centre pucker, and there was blue
05:13sky and purple clouds.
05:14I was hooked from that point on.
05:18But one of the other good ones I got, oh, Halloween Night 1985.
05:23The streak of lightning is actually coming up off of a transmitting tower, and I couldn't
05:27believe it.
05:28I chased storms four times on Halloween night, and at 17 minutes after 11 o'clock, thank you.
05:34And one of my other good ones, oh, for 1992, the best storm for 1992, capturing a bolt of
05:40lightning with the sunset, that's one thing, but capturing a bolt of lightning actually coming
05:45out of the cloud and into the sunset and down to the earth, that's so rare.
05:50What a great storm.
06:07Nobody can predict where and when a thunderstorm will form, but it starts with the formation
06:12of a normal cloud.
06:18Noel Williams is a physicist who spends his summers studying thunderstorms in New Mexico.
06:27Behind us we have a mature thunderstorm, it's weakly electrified now, but it's gone through
06:32its mature phase.
06:34That cloud formed very early on from water vapour, which is the fuel for the thunderstorm.
06:40Water vapour accumulates by evaporation from plants, from evaporation from lakes and streams
06:45and surface water.
06:47That water vapour then rises in the atmosphere, in thermals, in the boundary layer, and then
06:52it condenses.
06:54Condensation is the first stage of cloud formation.
06:59All clouds begin this way.
07:01Hot, wet air rises and condenses into droplets.
07:05If these grow large enough, they become too heavy for the rising air to support.
07:09rain falls.
07:16A thundercloud is made of stronger stuff.
07:18If the updraft is powerful enough, it'll pass the height where water condenses and continue
07:23upward.
07:24And the higher the air goes, the colder it gets.
07:28When the condensation proceeds and the vertical motion increases, you begin to form ice particles.
07:35You begin to, the cloud reaches a height where the temperature is less than zero degrees centigrade.
07:40You begin to form what are called grauple particles.
07:44Little ice crystals form and then the ice crystals begin to collect little water droplets and pretty
07:48soon you have little ice balls, which are about a centimeter in diameter.
07:52And when those little ice balls begin to collect, collide with ice crystals, that is the mechanism
07:58we believe to be responsible for the separation of charge.
08:04Separation of electric charge is what causes lightning.
08:10Five miles high inside the cloud, ice particles begin to form in the rising column of air.
08:16They can grow into hailstones the size of a fist, which hangs suspended in the upwelling
08:20air.
08:21Smaller, lighter ice crystals also form and are blown on upwards, rubbing past the larger
08:26chunks.
08:27And it's this rubbing that creates electric charge, negative on the large particles, positive
08:33on the small ones.
08:35The small ice crystals shoot on up to the edge of the stratosphere, which acts as a ceiling.
08:40They spray out sideways to form the characteristic anvil head of a mature thundercloud.
08:47It's 12 miles high and up to 15 across.
08:51The buildup of electric charge is enormous.
08:54Eventually, something has to give.
08:58Opposite charges attract.
09:00In effect, the thunderstorm is trying to pull positive charge away from negative charge.
09:05Eventually the atmosphere says, too much stress and breaks down.
09:10And that's when you get the lightning.
09:12Just as an earthquake occurs when the elastic forces within the earth reach a certain limit,
09:17the earth fractures and you get a catastrophic breakdown.
09:21They're both in the same category, lightning and earthquakes.
09:29Most lightning happens entirely inside the cloud, never touching ground at all.
09:43It lights the cloud from the inside, making what most of us call sheet lightning.
09:51But sometimes it does leave the cloud.
09:54Every year in the States, there are 40 million strikes to ground.
09:58Around 400 hit people.
10:00Perhaps half survive.
10:03When you're hit by lightning, you develop this arborescent pattern across your chest and
10:07arms as if a fern had been implanted there.
10:10And the first doctor I went to noticed this, and so he knew I'd been struck by lightning.
10:16They kept me overnight at that hospital and then released me.
10:19And I suddenly had this terrible feeling that I was going to die, that I just wasn't going
10:23to make it through the night.
10:26They figured out that I'd had a brain stem injury, that my sympathetic nervous system had
10:31actually been fried, and that my ability to maintain blood pressure or to keep my heart
10:37rate up was simply gone.
10:41And I'd lie there and think, how could such a thing have happened to me?
10:45I'm such a small thing, and the sky is so big.
11:06Most lightning doesn't happen where it's raining.
11:09Most lightning happens outside the rain, but there's usually rain between us and where the
11:14lightning is, but lightning doesn't like rain, because rain drains all the energy out of
11:19the system real fast.
11:21That's just turned out to be the worst thing about trying to chase lightning, is trying to
11:25get out of the rain.
11:38The End
12:08Oh, this is great. I'll tell you what, I just, oh, this year has been so bad because we haven't had any nighttime storms. But tonight, look at this, it's brewing. Oh, oh, yeah, it's here and I'm excited.
12:27Capturing anything of a lightning bolt is no mean feat. It appears randomly in or around a vast cloud that could form anywhere, anytime.
12:43That's a problem for scientists, too.
12:49This is Mount Baldy in New Mexico. It's the USA's second lightning hotspot with 50 lightning days a year.
12:58Perched on the peak at 10,000 feet is the Langmuir Laboratory. Scientists gather at the labs every summer because here they know where the thunderstorms will form. It's a quirk of geography.
13:09When the hot, wet summer wind meets the mountains, it's forced upwards. This assists the normal convection process and makes thunderclouds a virtual certainty.
13:21During the two-month lightning season, thunderstorms frequently form directly over the labs.
13:26But even taking up position underneath thunderstorms is not enough to guarantee close-by lightning for study.
13:35Thunderclouds are vast, maybe 15 miles across, and lightning may reach tens of miles sideways from them.
13:43So here, the researchers attempt to bring the lightning down where they want.
13:47They fire rockets trailing a wire behind them up into the thundercloud to channel lightning bolts to the ground.
13:52The basic idea is we use a simple model rocket motor that's housed inside of this model rocket nose cone.
14:00We have a conductor that extends from the tip of the rocket all the way down to the base.
14:05And as the rocket ascends, it pulls a very fine wire, 40-gauge copper-clad steel wire, that's connected to a stand which we use for current measurements.
14:15And a switch for the electric match that sets the rocket off that is activated by blowing on it.
14:23This provides us with an insulated signal line that allows us to launch the rockets from the trailer without endangering us.
14:30This is the trailer from which we trigger lightning.
14:38Rockets are launched from these tubes which are mounted here, each number being indicative of a certain position out on the launch pad.
14:45And the rockets are launched simply by blowing quite hard on the tubes like this.
14:52I didn't blow on it, but let's get the idea.
14:54KQP-492, this is the Cupola Tower to West Knoll.
15:06Would you please keep us surprised on any launch preparations?
15:13Close the ground, west, south, west.
15:14An electric field meter shows the charge on the mountain rising as the storm clouds' intense electric fields suck an opposite charge into the ground below them.
15:26Each time there's a lightning bolt, it drains some of the clouds' charge and the fields drop sharply.
15:36To trigger a strike, they must time the rocket launch perfectly.
15:40The aim is to fire when a natural lightning bolt is imminent and the electric fields are at their maximum.
15:52Kiva E-field, 2.5 km per meter, foul steady.
16:10The lab's research cameras capture every successful trigger on tape.
16:35Here, they can begin to lay bare the anatomy of the lightning bolt.
16:47on august 22nd 1957 i was struck by lightning on top of pike's peak that's the mountain in
17:11the distance over there and i met a young couple when i was up there i i took their picture and
17:17and they headed the opposite direction and a bolt of lightning came out of a little small
17:24thunderstorm the bolt stopped my heart stopped my breathing and knocked me up in the air about 10
17:31feet the lady said i came down on the ground came down i came down head first and got a concussion
17:37from it and the bolt actually exited out my feet and split the soles of my shoes her husband gave
17:45me artificial respiration and saved my life lightning kills more people than floods tornadoes
17:57or hurricanes attractive targets are metal equipment people in the water on the water
18:07or in open areas if thunderstorms threaten take cover
18:14the first and most obvious rule of lightning avoidance but even inside you are not completely
18:19safe in the united states about three people are killed every year while talking on
18:24on telephones this is a telephone earpiece you can see the electrical discharge here a spark went
18:31through the telephone out the earpiece into the person's ear killing him
18:40touching plumbing is not a good idea because the water pipes also go outside
18:44get immediately into a park vehicle a metal vehicle that's probably the safest place to be in a thunderstorm
18:57if you're outside you shouldn't make yourself the tallest thing around
19:01you shouldn't be out in a boat on a lake you shouldn't stand next to the tallest thing around
19:07like a tall tree because the tree is likely to get hit and then the lightning will jump to you
19:15the other risk under a tree is shrapnel the lightning runs through the tree's sap instantly vaporizing it
19:21a strip of bark can explode outwards at lethal speeds
19:36people say lightning never strikes twice but in fact i've been hit twice by lightning so that one
19:41goes out the window people seem to be afraid of me i was in montana recently near a famous trout stream
19:49with the big group of people and this terrible terrible storm came on just suddenly we were
19:54standing under trees right by the water all the worst things to do during the storm and i looked
20:00around and people were just backing away from me i couldn't believe it i mean lightning passes through
20:05you in a thousandth of a second and so at this point i'm really quite safe to be around
20:11which things will or won't get hit is still a mystery but that hasn't prevented extravagant
20:20claims from the lightning protection industry so perched on a hill at the langmuir laboratories are
20:2617 different designs of lightning rod the idea of a lightning rod is to protect an area by attracting
20:32any lightning strike that comes too close but there's no way to tell which designs work best
20:38some improbable and very expensive lightning rods are highly commercially successful here they're
20:44tested in competition with each other here are a couple of tips that we're testing this summer
20:50this one right here is a radioactive rod or tip as it is the real one has radioactive sources around the
20:58circumference in hopes that the ions released from this radioactive source will produce an ion cloud
21:04above the tip thus encouraging lightning to strike it this one here is called the blunt air terminal
21:10relatively easy to produce cheap as opposed to the radioactive source which might be about several
21:15thousand dollars others that we have up here on the mountain have electronic components inside
21:20which very alter their characteristics to try to make them better lightning attractors
21:25it's hard to get a lightning strike to hit one of our rods actually there are a lot of trees around the
21:30mountainside and those trees actually get hit more often than our lightning rods we've got 17 lightning
21:36rods but there's hundreds of trees it looks like james mathis may be researching this subject for quite a while
21:51at the moment we don't even know what guides lightning's jacket path or why it chooses to strike in
22:08one place rather than another all we do know is that the path is first created by a trickle of electricity
22:15that rushes outwards from a charged region high inside the cloud
22:21lightning strikes on the ground are more or less random they start in the cloud in a way we don't
22:26fully understand and then the lightning leader it's called the initial lightning process works its way
22:33down to the ground in in jerky steps with branches and it's generally thought that the lightning coming
22:41down from the cloud to the ground doesn't know the ground's there at all until the lightning gets
22:46maybe a few hundred meters above the ground but exactly how it goes through the air where it goes
22:52what the random processes are in between that brings it close to the ground and not well understood
22:58it begins as a small spark in the charged region of the cloud five miles up a spurt of electrons rushes
23:04outwards travels a hundred meters then stops and pools for a few millionths of a second
23:10then the stream lurches off in a different direction pools again and so on often the stream branches and
23:15splits there is very little current and almost no glow this is not a lightning bolt yet it's called
23:23a stepped leader an intensely charged channel leaping and branching down as it gets close its electric
23:29field begins to exert a pull on the ground
23:31the ground when that step leader is within 10 or 100 meters of the ground the ground is now
23:41aware of there being a big surplus of negative electricity which has come down on a conductor
23:46certain objects on the earth respond by launching little streamers up toward the step leader
23:53weakly luminous plasma filaments which are trying to connect with what's coming down
23:58if you happen to be standing there maybe a streamer is going to leave your head and and and head toward
24:03that step leader a telephone pole might launch a positive streamer a blade of grass might launch
24:08a positive streamer up toward the step leader it's that special one which makes the connection
24:14which gives rise to the return stroke and then this this catastrophic 10 000 ampere current flows that
24:21that closes the switch when that connection is made the electrons can drain to earth in a blinding bolt
24:29of light the part of the channel nearest the ground will drain first then successively higher parts of
24:35the channel and branches and finally the charge from the cloud itself so the visible lightning bolt moves
24:41up from ground to cloud as the massive electric currents flow down it happens at a third the speed of light
24:51the positive streamers only exist for a minute fraction of a second photographs of them are
24:59extremely rare here two streamers left the treetop and one of them successfully connected with the
25:05descending stepped leader so the lightning hit the tree a nearby telegraph pole also launched a positive
25:11streamer upwards but didn't connect a failed lightning bolt this is probably the only time a positive
25:22streamer has been caught on video the photographer here was very lucky if this streamer had been the
25:31one to connect it could have been fatal lightning always strikes twice in extreme slow motion you can
25:42see that this bolt is made up of many many strokes as the lightning finds new areas of charge inside the
25:48cloud and drains them one by one these are return strokes they happen in such quick succession that to
25:58our eyes lightning simply flickers on august 17th of 1985 i was photographing a storm at lake catherine near
26:18my home and a bolt of lightning hit three feet from me in that storm and literally threw me away from my
26:25equipment i landed on the ground about 15 feet away and when i got back up and i ran over to get my
26:31equipment i reached down to get my camera bag and three feet the other side of my camera bag there was
26:35a hole in the earth and it was still smoking and the photograph that i got out of that storm i call it
26:40the miracle because i'm still alive
26:48when lightning strikes the ground it just doesn't stop
26:51it goes into the ground and if the ground is not a very good conductor like florida sand
26:56it makes pads through the ground much like the pads it makes through the air
27:01this is an example of the path through the ground made by the lightning it's called a fulgurite
27:07the fulgurite is this tube of melted and solidified sand which goes down and in this case it contacted
27:16this power cable that's the actual damage done on an underground power cable it's basically glass
27:23if you look inside you can see that the inside of this tube is hollow and it's very glassy looking
27:29it's smooth there are also branches coming off which were destroyed in the excavation process
27:35fulgurites this length are relatively rare not because they're not all over the place but because
27:40it's very hard to dig them out they're quite fragile this doesn't happen when the ground is a
27:46good electrical conductor instead when the lightning enters the earth the electricity spreads
27:51outwards in all directions the lightning strike travels through the ground for hundreds of yards
27:57it hit jerry heard from 50 yards away through an umbrella he was sitting under
28:02leecher venal and myself in i think it was 1975 were playing the 13th hole at the
28:09chicago butler national in a tournament lead hit first i hit second then we're walking down the
28:15par three and a flash of lightning came over us i remember lee and i put our umbrellas over each
28:21other so we were kind of sheltering the rain light rain at the time and the second flash of light
28:26that was the one that hit us actually i guess the bolt hit close to the water or near us and we the we
28:32got hit where the umbrellas were touching us it was crossing lee in his back it was touching my groin
28:36area and that's where we got burnt then got hit and i remember my hands were shut from the
28:42contraction of electricity and i was thinking to myself i wasn't worried about dying but i was
28:48worrying gee my i can't open my hands i'll never be able to play golf again
28:54but i'm planning on going back on the seniors and we were very lucky and we we survived
28:58because golf courses are so exposed and so many people use them they present a special risk
29:06in the united states 20 of the people killed by lightning was struck while playing golf
29:11being caught anywhere in the open in a lightning storm is not a good idea although there are ways
29:16to minimize the risk if you're in a field and can't seek shelter try to stand with your feet very very
29:23close together and squat down you put your feet together to minimize the separation distance so
29:29that the current won't flow through your body it's no guarantee but it's better than nothing if you're
29:34in the middle of a storm if you count five seconds between the lightning and thunder that's one mile
29:39for every five seconds it's one mile that the lightning is away so the best thing to do is if your
29:44hair stands up that's an early warning system and if your hair stands up the best thing to do is drop
29:48straight down to the ground and just make yourself into a little ball don't lay on the ground just
29:53just squelch down and maybe the lightning will pick something else out above all don't play golf
30:02there is only one place that is entirely safe inside a metal box
30:13this cage at the boston museum of science is effectively that
30:16a metal box with a lot of holes in it it's called a faraday cage
30:21metal has a low electrical resistance so the current flows through the metal
30:25rather than through whatever is inside
30:32the more technology pushes along the in some respects the more dangerous things become
30:37for example we're trying to develop aircraft and even automobiles which are built of plastic
30:43graphite epoxy materials which do not form the nice metallic enclosure which one needs to have
30:50an absolute guarantee against lightning damage making sure that this doesn't lead to disaster is a
30:57full-time job andy plumber tests new aircraft designs against lightning
31:04airplanes are susceptible to occasional lightning strikes the lightning strikes enter one part of the
31:10aircraft and usually exit from another part like an opposite wing tip or a propeller blade or tail cone
31:17and continue on to a final destination for the lightning flash
31:23here for example is the effect of a severe lightning strike on a piece of a typical aircraft aluminum skin
31:31material the lightning makes a small amount of pitting and a slight amount of melding but not a complete
31:38puncture however airplanes are being fabricated today also of carbon fiber composites which have
31:45less electrical conductivity and so the same severe lightning strike may cause a significant amount of
31:52damage and even a complete puncture of such materials unless adequate protection is applied to the composites
32:00here is a piece of the same carbon fiber composite airplane skin material that has been protected with
32:09a fine woven copper mesh and you can see that there's much less damage just a little bit of cosmetic effect
32:17and no effect on the back side of the material at all
32:20a plane's fuel tanks need particular attention this test chamber is designed to ensure that if a tank is struck
32:30no sparks will appear inside it the test chamber that you see here is used to evaluate whether or not
32:38a lightning strike might result in an ignition source a small electrical spark that might occur inside the fuel tank
32:44and ignite fuel vapors so here we have a chamber into which we can put flammable fuel vapors and then we
32:53may insert a wing skin on one end of this chamber right here we strike this skin with 200 000 amperes
33:01through this conductor and this electrode here to the surface of the skin and determine whether or not
33:08a spark or hot spot might exist on the inside surface of the skin if the skin covering the fuel tank test
33:15chamber is defective the strike will create a spark inside the chamber and the fuel will explode through
33:20the foil cover so in this case it's back to the drawing board sparks have penetrated the tank and ignited
33:32the fuel if this had happened to a real plane in flight the results would have been disastrous
33:38testing is vital the average airliner can expect to be hit once every year despite the fact that
33:49pilots go to great lengths to avoid thunderstorms or rather most pilots
33:57in the 1980s nasa flew a fighter plane straight through the most violent thunderstorms they could find
34:03they wanted the plane to be hit as often as possible to learn exactly what happens during
34:07a plane strike they were more successful than they'd ever hoped the plane's metal body compressed the
34:13storm's electrical fields as it flew through them it was their presence that triggered the thunderbolt
34:19strike to the aircraft no triggers that was a nice boom we are learning to protect our world from
34:34lightning but in the process we are also discovering that perhaps we need it without it we might not even
34:42be alive
34:53so
34:55got it boy man did you see that one i think there's more to
35:24lightning than just a a powerful something that's happening out there and and the more we
35:30the more we play with it it's like me and in 20 years that i've been doing my work i've learned
35:34a lot about lightning and there's a lot of intrigue there's a lot of fear there's a lot of awe there's
35:42a lot of feelings that people feel when a lightning storm is around and i believe that yes it goes a
35:49whole lot farther than just science there have always been myths and legends about lightning
35:55for millennia people have seen mysterious balls of fire floating slowly through the air during
36:00thunderstorms stories of ball lightning are still alive today
36:09i was driving home when it was raining very heavy and i turned into the driver and as i
36:13turned in the driveway was waiting for the garage door to open i heard this tremendous bang and a
36:19big flash the ball of lightning was about the shape of a shape and size of a bowling ball it was red and
36:27orange and a little bit of blue and it looked very glassy almost and i saw it out the window it came
36:34from up in the sky and then it almost curled around and it struck near the front wheel
36:45but there was nothing there no no hole or any sign of it even being there
36:53often the people who witness these events don't come forward afraid they will not be believed
36:58perhaps rightly there are photographs that are claimed to be of ball lightning but they're vague
37:07and inconclusive much like photos said to be of ufos it's easy to be skeptical ball lightning is is a
37:14very um interesting area of unsolved problem in lightning research and and it doesn't have a very shiny
37:22reputation at the moment but there's so many stories suggesting that they're luminous balls of plasma
37:28which last for many seconds there's some interesting reports from the submarine community the old navy
37:35subs they had large battery banks and occasionally they would see luminous fireballs when there were
37:41accidental short circuits of these large battery banks many scientists think there must be some truth
37:48in all the stories but there's one researcher who not only believes in ball lightning but claims he can
37:54make it so here's one for all you folks who love a little mystery
38:00you shake my nerves and you rattle my brain too much love drives a man insane you broke my will
38:07but what a free goodness of grace great balls of fire
38:13love what i thought it was funny you came along
38:16whoo now honey i've changed my mind this good is fine
38:30all lightning ranges and sizes from you know an eighth of an inch up to maybe uh basketball
38:37sizes some people have claimed three feet uh now i don't i don't know if that's really
38:41ball lightning the type of ball lightning i'm looking at it might be still a different phenomena but
38:46it floats around it can get buoyant go up it can come down it can disappear slowly or it can
38:52disappear with an explosion
38:56the experiment that you're going to see it consists of 20 submarine storage batteries these are like 25 000
39:03amp hour batteries all connected in series which gives us gives us about 42 volts at maybe 18 000 amps
39:18okay the positive side of the battery is connected to this terminal and the negative is to the bottom
39:24plate here and the entire battery bank all the electromotive energy is developed across the short
39:31circuit gap when i bring those together and we use a little bit of water to keep everything cool and
39:36to keep the ball lightning in one place robert golker is the only person in the united states and one of
39:42only two in the world who says he can make ball lightning to order
39:51he claims that these grape-sized fireballs are the lab equivalent of ball lightning
39:55his theory is that when lightning strikes something the violent heat flakes off tiny fragments these
40:01become partly vaporized and are buoyed up on a cushion of incandescent gas
40:16you're getting a metal vapor that's swirling and moving around very fast rotating very fast around
40:32usually a liquid metal droplet very small maybe the size of grain of sugar and these with something the
40:40size of grain of sugar we can get fireballs up to about a quarter of an inch now how these things will
40:46scale to two or three or four inch or basketball size i'm not sure but that's what i'm trying to
40:52find out now and that's why i've got 500 submarine batteries to make a lot of current
41:01golker's ideas are not widely accepted some scientists still question whether ball lightning even exists
41:08and even if it does not everyone would agree that this is ball lightning or that conventional lightning
41:13could make it in this way the jury is still out if you look at the distribution of currents and lightning
41:19the averages are sort of 5 000 10 000 15 000 amperes not unusual but if you go out in the tail of the
41:27distribution you find these whomping big currents sometimes two three hundred thousand amps
41:32the value of what golka is trying to do is he has a bank of batteries which will enable him to explore
41:41this region we know that if ball lightning has any reality um it's a very rare phenomenon it doesn't
41:52happen in every thunderstorm it's something which happens once in a blue moon but at least i tend to
41:57believe that something is going on something something we don't understand but something real
42:04other stories of mysterious events around thunderstorms are closer to being resolved
42:09for decades pilots have reported seeing brief flashes in the sky above storms
42:14the reports were ignored
42:19but perhaps they were true this research footage was taken a few months ago above the massive lightning
42:24storms of the american prairies scientists have nicknamed these flashes sprites they're almost too faint to
42:31be visible and last a fraction of a second they're 10 miles wide and reach over 50 miles straight up from
42:38the top of the storm and until two years ago no scientists had any idea they were there nobody yet knows what
42:46they are or how the storm creates them their power and their effect on the atmosphere are still mysteries
43:02there's a whole ancient mythology surrounding lightning for example zeus running across the sky holding
43:09bolts of lightning and chinese goddess flashing mirrors and a thunderbird rising up out of a mountain
43:16i think myths are the stories that we tell ourselves in order to cope with these great cosmic events
43:26they frame our imagination and also our fears
43:34perhaps that's not surprising
43:38before human beings even existed lightning was the main source of fire on earth
43:42many of the world's forest ecosystems have evolved to take advantage of lightning fires
43:49trees whose seeds need fire to germinate exist because of lightning others colonize the areas that fires
43:55lay bare
44:06at its peak the temperature of a lightning bolt hits 50 000 degrees and the air itself burns
44:14nitrogen and oxygen react together to make nitrates vital plant fertilizers which rain to earth
44:20lightning provides our planet with a third of one of its most vital chemicals
44:29lightning has been around for a long long time
44:32lightning might have been the origin of life on earth in fact
44:36in the primordial soup it might have created the chemicals from which life evolved
44:44many aspects some that we understand probably most that we don't of life on earth
44:50is related to the fact that lightning has been here virtually forever in fact in in england fulgurites
44:57uh the glassy tubes uh the lightning makes in the in the sand have been dated to be 200 million years old
45:07and certainly lightning was around before that
45:11only looking from space can you appreciate the real scale of lightning on earth
45:28images from a low light level camera on the space shuttle show nighttime storms flickering across entire continents
45:41images from the sky
45:50but it's not just the earth
45:54there is evidence for lightning on other planets in the solar system too
45:58on jupiter it's actually been photographed
46:01this violent flash of light a thousand miles long was caught by one of the voyager probes as it passed
46:06perhaps there was lightning everywhere
46:13on earth all it takes to make lightning is damp hot air to create thunderclouds
46:17so the more heat the more lightning
46:22this has led earl williams to explore a startling new idea using lightning to measure the world's temperature
46:31well about five years ago i embarked on an expedition to tropical darwin australia
46:35where some of the largest thunderstorms in the atmosphere form these storms go to about 20 kilometers
46:40altitude they make continuous lightning one lightning flash per second they're real giants
46:48one thing we noticed right away was that when the temperature rose by one degree centigrade
46:53the lightning went up by four to five fold what he realized was that if a higher temperature meant
46:58more thunderstorms in australia the same thing ought to happen everywhere if the whole planet warms up
47:04there ought to be more lightning find a way to measure the increase or decrease in the amount
47:09of lightning across the planet and in theory you could use it to measure changes in the earth's temperature
47:15how do you monitor lightning on a planetary scale it turns out there's a natural framework
47:21for doing this it's called schumann resonance every lightning is like a little radio antenna which
47:28which transmits radio waves over a broad range of frequencies it turns out the earth is tuned in
47:34the schumann resonance to one frequency and just as you tune in a radio station on your radio you can
47:40tune in the schumann resonance at eight cycles per second and at that frequency you can listen
47:45to effectively all the lightning on the planet the sound of more than a hundred lightning bolts a second
47:56scattered around the globe each one creates a burst of radio waves that travels right around the earth
48:03when the earth warms slightly the volume increases when the earth cools there is less
48:08but this technique cannot yet be used to search for evidence of global warming
48:13that would require schumann resonance records going back at least a century and we only have them for
48:18the past 30 years we are just beginning to realize how intimately lightning is bound up with the living
48:26processes of our planet perhaps we owe it to our future to learn to understand it better i was struck by
48:35lightning three years ago and i'm still i think in the process of recovery my life changed completely
48:42after i was struck everything i was everything that i did was taken away stripped away and in a way i
48:50still find lightning storms fabulously beautiful i just i can't stop going out into storms and even
48:57though i stand there and wonder how it ever entered me i just love to watch them i think i always will
49:14too much rain
49:28a lot of people think that i have a death wish because i stand under lightning bolts but no i have
49:32a life wish
49:37i've been in lightning for 20 years now and if i have to go you know and when god calls me home if i
49:44have to go i'd rather go by one just major bolt of lightning and take me out and then maybe i can be up
49:50there running the lightning machine see
49:59can the lessons of the past help us to face our future peter hennessy looks back at rations and russians
50:05post-war britain explored in what has become of us next
50:20a perceived new age a renaissance of unprecedented magnitude a digital highway
50:38to cyber shopping cyber games these kids are natives in a land where the rest of us are immigrants
50:45i just hope that the kid can cut it even cyber sex i think people are really losing sight of where
50:53we actually come from who's controlling who in cyberville next sunday at seven on four
51:03if you would like to discuss any of the issues raised
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