Original subtitles

WILLIAM SHATNER: Devastating earthquakes

that ravage entire cities,

erratic balls of lightning that appear out of thin air,

and a massive cataclysm that blocked out the sun

and blanketed the world in darkness.

There is nothing more humbling than the power of Mother Nature.

(thunder crashing)

For as long as humans have inhabited the Earth,

we have tried to decipher just exactly how our planet works.

Our survival has relied on learning to predict the weather

and creating safe shelter from natural disasters.

But even today, we are often faced

with terrestrial events that are beyond conventional explanation.

How much do we really know

about the strange forces of nature

that happen all around us?

Well, that is what we'll try and find out.

♪ ♪

Across the city, a celebration is underway.

Thousands of Christians are

packed into churches to celebrate a festival known

as All Saints' Day.

But then, at about 10:00 a.m.,

without warning...

disaster strikes.

MICHAEL WYSESSION: A massive magnitude-eight earthquake occurred

in the Atlantic Ocean seafloor

right along the tectonic plate boundary

between Eurasia and Africa.

The shaking from this earthquake

knocked down about 85% of the buildings of Lisbon.

Even worse, this earthquake occurred

while most people were in mass,

in church or cathedrals

on All Saints' Day.

Lisbonites are in all these churches,

and many of the most major churches

in Lisbon were destroyed.

It was one of the most devastating earthquakes

that Europe had seen in centuries.

SHATNER: In a matter of minutes, the massive earthquake

reduced the buildings throughout Lisbon to rubble

and opened a 16-foot-wide crack in the ground

through the center of the city.

Estimates place the death toll as high as 50,000 people

or about 20% of Lisbon's population.

WYSESSION: In the early 1700s,

if you had listed the five great cities of Europe...

...you well might have included Lisbon in that list.

But after 1755,

Lisbon's glory was reduced, literally, to ashes.

Lisbon rebuilt

but never really reached the same glory that it had.

SHATNER: In the aftermath of the horrific quake,

the residents of Lisbon struggled to understand

why this tragedy had befallen their city.

Many among the Christian populace

who had only heard of such devastation in the Holy Bible--

believed the earthquake to be an act of God.

Lisbon was dominated by the Catholic Church.

Very, very religious city.

So lots of theologians started to ponder

the meaning of this event in religious terms,

because the fact was, this earthquake had struck Lisbon

on one of its holiest days, the Feast of All Saints.

It had killed tens of thousands of Christians

while they were worshipping.

Why did God choose this day

to bring an earthquake upon the people of Lisbon?

And this was a confrontation for many theologians

and they blamed the people of Lisbon.

They said, "You must have been sinful."

The only reason this could have happened to you is

that you are not living by God's laws.

SHATNER: While some people thought

the earthquake was a punishment from God,

others focused on taking practical steps

to guard against such a calamity in the future.

One of those people was Portugal's prime minister,

the Marquis de Pombal.

McNAB: In the reconstruction of Lisbon, Marquis de Pombal oversaw

really critical innovations.

The first is to build earthquake-resistant buildings.

These are built around wooden frames that can actually

sway with an earthquake, rather than collapse.

And then, he improves the city.

Before, it was these winding, medieval streets

which people could get blocked up in.

So the Marquis de Pombal,

he redesigns the city on a gridiron system,

so all of a sudden you have now, really wide,

straight streets, which are ideal for evacuating people.

And in fact, the way that he handled

the reconstruction of the city

is the first instance of modern disaster response in history,

where someone actually tries to take a rational response

to the effects of a natural disaster.

SHATNER: The varied reactions to the Lisbon earthquake

have actually been quite common throughout human history.

For thousands of years, mankind has tried to make sense

of these violent tremors

that often strike without warning.

Earthquakes have a really unique place, uh,

in human consciousness because

you can't see it coming.

It's not like a giant storm

that you can see the clouds approaching,

see the lightning, hear the thunder.

Earthquakes, you feel and you hear,

but that happens in the moment.

You can't run out of the way.

There's nowhere to hide.

The problem of earthquakes

and how to deal with them

goes back to antiquity.

The first seismometer, to measure earthquakes,

was actually invented by a scientist named Zhang Heng

back in China in the first century of the Common Era.

This was a beautiful bronze-- almost like a cask

that had dragons around the perimeter

with balls in their mouths.

And beneath them were a little array of, of bronze frogs.

And the way the device worked is

the pendulum inside would rock just so,

bumping a lever in the direction where the earthquake occurred

and a ball would fall out of the dragon's mouth and land,

telling you the orientation

of an earthquake that had happened.

And all developments since then on earthquake detectors--

we call them seismometers--

have been variations on that theme.

SHATNER: Today, experts understand

that earthquakes happen when massive underground rocks

known as tectonic plates suddenly collide,

causing seismic forces to be unleashed beneath our feet.

Scientists can measure an earthquake's power

and even pinpoint its location.

But in spite of everything we've learned,

we still have a hard time predicting where

and when the next earthquake will strike.

PHOENIX: With earthquakes,

there's still a component of uncertainty.

And we are always

trying to improve our earthquake knowledge.

We actually have

extensive seismic networks that go all around the globe,

where you can have an earthquake in China that we sense

in Virginia on a college campus.

And that helps us really triangulate

where these events occur,

how deep in the crust they occur,

and how big they really are.

We've made huge amounts of progress,

but there is still so much more we have to learn

that will help us understand

where and when these quakes might happen

so that we can save lives.

SHATNER: While scientists haven't learned how to predict earthquakes,

a curious theory about what causes

some of them to occur has emerged.

And it just so happens

that humanity may, in fact, be to blame.

McGEE: The idea of human-induced earthquakes

really comes to the forefront of the, the social mind

in construction of the Hoover Dam

in Nevada in the 1930s.

It actually triggered a series of earthquakes

around the dam under construction.

We think we can create gigantic reservoirs

without facing consequences of these things.

But if your reservoir is near a fault line,

watch out.

There is a theory that a lot of seismologists believe in

that the earthquake of 2008 in China

that killed about 70,000 people

was, in fact, created by this gigantic reservoir

that put enormous pressure on a fault line

which then gave way.

What happened in Sichuan in 2008

is a wake-up call.

A wake-up call in that when you tamper with the Earth,

you're tampering with an earthquake.

SHATNER: Is it possible that some of the deadliest earthquakes

in modern times were caused,

not by nature but by human activity?

Either way, scientists are still at a loss

as to when the next catastrophic earthquake will strike.

Not unlike another dangerous phenomenon

that can appear without warning.

It's a burst of mysterious energy that is known...

as ball lightning.

SHATNER: While out for an afternoon stroll,

a local student spots something that stops him in his tracks.

Pulling out his cell phone, he captures incredible footage

of an eerie ball of what looks like pure energy,

floating and bobbing, as if alive.

Later analysis reveals that the video may be evidence

of one of the most mysterious weather anomalies in the world:

ball lightning.

MICHAEL DENNIN: Any video of ball lightning

is exciting and interesting to me because they're rare.

It's hard to see it.

And it does confirm the idea

that what you're really trying to look at

is some sort of contained plasma-like object.

TAYLOR: Looking at this video,

what's happening is this ball lightning

is probably traveling along the electromagnetic field line

of the power lines.

And then, when it hits the, uh, transformer,

it's just too much power for the transformer to handle

and it explodes.

And you can see that in the video.

SHATNER: Unlike normal lightning,

which follows well-defined laws of physics,

ball lightning is much more erratic in its behavior.

Even after centuries of research,

scientists still don't really know what causes it.

Or where this incredible energy comes from.

When we think of a lightning bolt,

we think of electricity shooting from the heavens,

just crackling with energy...

...which is totally different than ball lightning.

Ball lightning is basically a sphere a few feet across

that seems to hover slowly and then dissipates.

So, how can that be?

Ball lightning is essentially lightning in a bottle,

but there's no glass bottle,

there's an electromagnetic bottle.

So you get these electromagnetic field lines

that form the shape of a sphere

and it traps the lightning inside it.

It can range in size from pea-size to dime-size,

baseball-size, grapefruit-size.

And the uniqueness of ball lightning

is it lasts from 20 to 30 seconds,

unlike a regular bolt of lightning which is just a flash.

Ball lightning has been mysterious for so long

because it's hard to capture.

'Cause when it happens,

the ball is skittering and moves around crazy,

it doesn't just sit there in one spot,

so you can't walk up to it and look at it.

SHATNER: Is it possible that sightings of ball lightning

are just a trick of the eye?

An optical illusion?

Or could ball lightning be responsible for everything

from mysterious UFO sightings

to strange accounts of a phenomenon

known as spontaneous combustion?

Ball lightning was first discovered in the 1600s

in a European church when the ball lightning

came right through the window and into the sanctuary.

KAKU: There are many documented eyewitness accounts,

not just one but scores of them through history,

of ball lightning entering people's homes

and being cited by reputable witnesses.

The most famous sighting was done in Russia

by Czar Nicholas II.

He had an eyewitness right in front of the royal family.

A ball lightning went whizzing right by, and he wrote about it.

People just say, "Oh, no, I was standing there

"after this thunderstorm in my living room,

"and this ball of light came across the field,

"right through the picture window into my room,

and touched the steam radiator and popped like a firecracker."

And I have not read an explanation

for that behavior that I consider plausible.

EVANS: It's believed that glass actually

enhances ball lightning.

The trace elements in glass, including lead,

is very attractive and a conductor of lightning.

And we always say, "Stay away from water

and glass windows when there's lightning,"

because those are conductors.

And it seems that ball lightning

is very attracted to glass

and will actually pass through it

and then can create a lot of damage.

Ball lightning can be very dangerous.

It's started fires, it has put buildings on fire.

It has caused a lot of destruction

just in and of itself.

SHATNER: If it sounds impossible for a primal force of nature

to be contained indoors, well, you'd be wrong.

Because, as it turns out,

scientists have done just that.

In 2006, Professor Eli Jerby

and researchers at Tel Aviv University

used powerful microwave beams

to generate a tiny sphere of plasma

for fractions of a second.

It was the first time

anything resembling ball lightning

was reproduced in a laboratory.

TAYLOR: It took scientists a long time

to reproduce ball lightning in the laboratory.

Ball lightning needs a lot of energy.

And the way you would create that

is you have really strange high electromagnetic fields

that are wrapped around each other that traps

and squeezes the air molecules until they're so hot

that they become ionized and, literally, are like

a big ball of plasma, like a little mini-star.

SHATNER: Could ball lightning

actually be some kind of "miniature star,"

one that exists here on Earth?

According to some scientists,

the notion is not as far-fetched as it sounds.

Which could also mean that ball lightning

has the potential to develop

into one of the most destructive forces

in the known universe.

TAYLOR: Some people suggest that ball lightning

could be primordial black holes.

Primordial black holes are very small, microscopic black holes

that, uh, would have formed at the beginning

of the Big Bang or just after.

And it's possible there's still some of them,

remnants of the Big Bang, floating around in the universe.

DENNIN: When I look at ball lightning, it just seems such a clear

ion electromagnetic effect

that it's probably not even necessary

or likely to be connected

to something like micro black holes.

But there's nothing necessarily in physics that tells you

it's impossible to have it happen.

(electricity buzzing)

SHATNER: In northwestern Poland,

just outside the village of Nowe Czarnowo,

stands a grove of pine trees unlike any other.

Instead of rising straight up to the sky,

these trees bend, bow...

...and buckle

in a most curious, and some would say, unnatural fashion.

Which is why this place has come to be known

as the Crooked Forest.

WYSESSION: When you see this forest, it's very striking.

Trees come up initially straight,

and then they take a sharp bend all to the north

and eventually curve back up again.

And to see, maybe, one tree grow this way

might not be unusual,

but to see a whole grove of trees grow this way,

clearly something was at work.

SHATNER: Although scientists have dated the unusual trees

to the 1930s,

local records became lost after the end of World War II.

The only thing we know for certain

is that these are otherwise normal pine trees

that, for whatever reason, didn't grow straight.

SLOAN: I don't know of anywhere else in the world

that we could walk into a forest

and see such broad, dramatic, sweeping curves

throughout the entire stand.

And so, there have been a lot of questions,

a lot of speculation as to what caused this.

Everything from tank maneuvers that might have occurred

in the area around the time of World War II

to snow and wind loads on these stands

to chemicals that might have been in the soil

or genetic questions that might be at play.

I think most of the natural processes would-would cause

a much more sort of gradual curve or lean in a tree,

but not such a distinctive sort of hook shape.

In this case, the fact that it's very consistent

and more extreme than you would typically see

in any sort of natural situation

would suggest that it was probably human manipulation.

But we'll never know for sure if that was the case.

WYSESSION: One possible explanation

comes from records of timbers called compass timbers

that were trees that were grown particularly.

They were pruned much like topiaries or bonsai trees

to have a curved shape, and these timbers were used

in the hulls of ships.

Rather than trying to bend boards with steam to make ships,

they actually grew trees that already had that curved shape.

Whatever happened to these trees

most likely happened when they were very young.

This obviously would have taken

a lot of thought and work on the part of somebody

to go out and plant this forest,

to go in and prune or otherwise manipulate

these young trees and tend them

to create this kind of a big, sweeping bend.

And then, that raises the other part of this mystery:

what changed that nobody came back?

WHITEHEAD: So, the idea that humans cultivated these trees

to make furniture or for some other manufacturing purpose,

it doesn't really add up.

The question is, why would anybody go

to that kind of trouble?

And, I mean, we're talking at least ten years

to produce a tree with that kind of bend,

only to disappear when it comes time to harvest them.

SHATNER: If the Crooked Forest isn't the result

of some arborist's bizarre plan, then what else could explain

the tree's strange and contorted shapes?

There's got to be something more to this.

Maybe it's something that we haven't yet thought of.

Could it be that these trees have some kind of capability

that we have yet to fully understand?

In Native American traditions,

um, plants have spiritual essence,

or you might say souls, plants have souls.

And in that sense, what we might think

in terms of being a person or having a consciousness.

Amongst our people, the trees, they-they do have a spirit.

Not only trees, but everything.

But mankind, we don't see that, we don't understand that.

WHITEHEAD: We see this also in Japanese culture,

where they talk about nymphs and spirits

that inhabit the trees.

And even in the Druid traditions,

they wouldn't even approach a tree

or walk underneath the leaves of a tree

without asking permission.

They would speak to the tree.

SHATNER: Is it possible that the pines of the Crooked Forest

are actually capable of communication?

While such a notion may seem far-fetched,

scientists are beginning to discover that trees

and other plants have far greater capabilities

than previously known.

FISHER: When you step into a forest,

all the trees around you are not just isolated organisms.

They're actually a community

that are communicating with each other.

Forests are more often, uh, connected underground

through their root systems by fungal mycelia,

which are basically little threads of fungi

that tap into the roots and then connect that tree

to other trees that it's also connected to.

WHITEHEAD: So, the question is, is there an advanced form

of consciousness, in a way, that inhabit trees?

And even in the scientific world,

they've been changing the way that they look at trees

and they've been seeing that trees possess

a sort of intelligence,

where they communicate amongst each other.

Did the trees of the Crooked Forest in Poland

somehow choose to grow in a twisted and unusual shape?

It's a fascinating theory and suggests

that we have to think outside the box

in order to understand strange forces of nature.

Like in the case of an inexplicable storm

where thousands of fish...

mysteriously fall from the sky.

SHATNER: Residents awake to a flash of lightning

and what sounds like hail falling from the sky.

But surprisingly, what is really raining down on the city

is not hail...

(thunder crashes)

...but fish.

EVANS: The images are so bizarre,

when you first see them, you think

this must be some kind of a hoax.

Fish falling from the sky.

And they're everywhere.

THOMPSON: If you're out in the middle of a small village

and all of a sudden, it's raining fish on you,

most people will wonder, you know, why?

What does this mean?

SHATNER: I am sure you're all familiar with ancient stories

that tell of frogs raining from the sky.

Most consider them myths, but in actuality,

the phenomenon of live creatures showering down from the heavens

is all too real.

When you think about it, it's really mysterious.

How could it possibly be raining fish?

Since the tenth century, there's been records

of fish falls from the sky.

Small fish from all over the world

have fallen from the sky.

I know a story my dad tells me when he was a kid,

about ten years old, that it rained so many fish

in his front yard that they picked them up

in wheelbarrow loads and had a big fish fry.

KAKU: When you look at anecdotal data,

there are many instances in the past

where it's raining fish.

And you say to yourself, how can that be?

That seems to violate

everything we know about storms and common sense.

DENNIN: The reality is, tornadoes are regularly taking stuff

from one place and dropping them somewhere else.

But they're over land and they're definitely

moving things that are typically land-based,

so obviously they're not going to drop fish

because they're over land.

But basically, a waterspout or a tornado over water

is conceivably going to have the same effect.

It can suck things out of the water.

And then as that object continues to move,

it moves across land.

At some point, those will fall back out of the tornado

and it will look like raining frogs or fish.

FISHER: It's not implausible.

I don't think it's a coincidence that most of the animal rains

that we experience are-are aquatic animals, right?

Because those are probably the ones that are easiest

to suck up in a waterspout and then deposit on the earth.

SHATNER: The notion that a waterspout

could siphon tons of fish from the sea--

before raining them down miles away--

is one that is supported by many scientists.

But if it sounds far-fetched to you,

you're not the only one.

People have watched waterspouts over lots of places,

and they never seem to see anything

being scooped up out of the ocean by waterspouts

that we've actually watched for a long time.

Whatever this phenomena is, it happened very quickly.

If you take a fish out of water, it is fighting for breath.

It's going to, uh, suffocate.

And that suggests-- is there some other thing at play?

Like, could there be some strange physics

we don't know yet?

EVANS: What's really strange about the fish fall in Yoro

is that it happens about the same time every year.

It happens so often,

they have a name for it, Lluvia de Peces,

which means "raining of fish."

So, it couldn't be a waterspout.

It has to be something more to it.

SHATNER: If Lluvia de Peces can't be explained

by random waterspouts, then what could it be?

According to some scientists,

the answer could be even stranger than...

well, fish falling out of a clear blue sky.

MIKE BARA: There are places on Earth,

like the Bermuda Triangle in the Caribbean,

where you do have these

very, very strange occurrences that happen.

People talk about flying into these electronic fogs.

BRANDENBURG: I think you have to have some new physics involved

besides just a waterspout.

Matter is inherently electromagnetic.

And so, if you have a bunch of moving gas or liquid,

then you are actually creating a flow of-of electromagnetism,

which could create a vortex disturbance

that may have allowed this phenomenon.

It's as if you can create some kind of spacetime portal

that, uh, transports these fish or frogs.

Just the waterspout explanation

seems barely plausible to me.

SHATNER: Could interdimensional portals

be what causes fish to suddenly appear

in Yoro every year?

Perhaps. But for the people of Yoro,

the question is academic.

As far as they're concerned, the fish are a welcome sight,

no matter what brings about their arrival.

If you look at the people of Yoro,

they go outside and they pick up all this fish for dinner.

They put it into buckets. It's a positive thing.

So if we look at it like this,

we take something that's out of our sphere of knowledge

and we deal with it.

EVANS: In ages past, fish falling from the sky

was the wrath of God.

I don't think we're afraid anymore.

But I also think that there are some things about weather

that we may not understand, we may never understand.

But that's okay.

(thunder rumbling)

SHATNER: Spring has arrived in the capital

of the Byzantine Empire.

But even though winter has ended,

the temperature remains cold,

because the sky is so dark...

that it blocks out the Sun.

PHOENIX: What is really astounding

is the way that people described this 536 event.

You had writers explaining what happened

in very precise detail from what they could observe.

They describe the Sun became darkened

and we felt a thickening in the air

and we saw this fog or this dust veil.

Now, they didn't know what caused it,

but the descriptions are extremely thorough.

WYSESSION: The Byzantine historian Procopius

wrote that the Sun shone at half its strength,

like it was in eclipse.

This was the start of a period

of colder-than-average temperatures.

And that darkness lasted for 18 months.

SHATNER: The Sun was blocked by a dark sky for over a year?

Such an improbable catastrophe

may sound like it was a fictional story

taken from the pages of ancient folklore or mythology.

But, curiously, numerous historical accounts

of this event were written,

not just in Constantinople but all over the world,

during the year 536 AD.

What happened in 536 was a climate event

of considerable magnitude that was

terrible for the people who lived through it.

The most detailed record is in Latin.

And it was written by Cassiodorus,

who was a high civil servant in Italy.

He wrote that the Sun gave off no warmth

at any time in the course of the day.

And there are also records in Chinese that refer

to a terrible cold,

terrible freezing in the summertime.

And so we've been able to piece this story

of this extraordinary catastrophe together,

combining the evidence of sources

of eyewitnesses who wrote their reports in Greek,

in Latin, and in, uh, Chinese.

The Earth became cold,

the crops died.

The result was tremendous food shortages,

hunger,

famine in places...

...migration, and upheaval.

SHATNER: It is clear from the historical record that,

starting in the spring of 536 AD,

the entire northern hemisphere experienced

darkness and bitter cold for over a year.

In fact, historians have dubbed 536 AD

"the worst year to be alive in history."

But what could have caused the Sun to become blocked

in the first place and for such a long period of time?

Numerous theories have been proposed, including the idea

that an asteroid impact sent dirt into the atmosphere.

But in recent years, some scientists have suggested

the darkness may have been caused

by a volcanic eruption.

KAKU: When you think of a volcano, you have an image of lava flows

oozing out of the volcano.

Well, yes, that's what happens,

but that's not the only thing which happens.

You also have all the soot and debris,

which blanket the atmosphere and block out sunlight.

And so in 536, we think

that there was a volcanic eruption

and there was so much soot, ash, debris

launched into the atmosphere, that it created a fog.

A fog that destroyed agriculture.

A fog that ground civilization to a halt.

PHOENIX: This event around 536 has all the markings of

a very large-scale eruption that had the ability to change

climate conditions all across the northern hemisphere.

It really does emphasize

just how big the effects

of volcanoes are, how widespread

and how damaging they can be to human civilization.

SHATNER: But if a volcano caused the year of darkness,

then which of the nearly 1,500 active volcanoes

on Earth was the one that erupted?

McCORMICK: A team working on the ice levels for 536

from the Swiss Italian border found microscopic

morsels of volcanic particles

that matches what one

would expect in a volcano in Iceland.

And so, the top suspect right now

in the eruption behind the 536 event is

one of the many volcanoes in Iceland.

SHATNER: Scientists are still working to definitively prove

whether a volcanic eruption in Iceland

blocked the Sun in 536 AD.

But perhaps the even more pressing question is,

could the Earth ever be blanketed in darkness again?

Could this happen again?

The answer is, of course, it could happen again.

It has happened once in the last 2,000 years.

It has perhaps happened more frequently

over a longer time span that we have not yet

been able to uncover.

We need to be prepared.

The 2010 eruption of Eyjafjallajökull,

the Icelandic volcano,

actually disrupted a lot of people's lives

because volcanic particles

were going up into the atmosphere.

And it shut down air travel,

because those particles

will clog your jet engine and cause major, major problems.

This planet has a beating heart.

It has life.

It is an ever-evolving,

ever-changing process every time a volcano erupts.

And we are just along for the ride.

SHATNER: Located along the Detroit River,

this Canadian city seems,

by all appearances, to be quite normal.

But if you listen closely,

you'll hear something strange.

(mechanical humming)

Do you hear it?

That humming noise?

Well, if you do, be careful.

It may just drive you mad.

WYSESSION: About a decade ago in Windsor, Canada,

people began hearing a hum.

Some people, not everyone, and not all the time,

but this was a serious, significant hum.

GEORGE NOORY: I was born in Detroit,

and I would go to Windsor, Canada quite often

during my days as a reporter in that city.

People are hearing a strange hum that affects them.

It literally drives them crazy.

And nobody's been able to pinpoint

exactly what's happening.

(low mechanical humming)

Most people would describe it as a very low frequency,

modulating sound,

or they'd characterize it

as a large diesel truck or even

train locomotive parked outside

their window, chugging away.

Sometimes I get like a-a rumble,

like almost thunder.

But it's definitely not thunder.

It changes from one moment to the next.

Sometimes we get four hours, sometimes we get

four days, four weeks.

Sometimes it's nonstop.

DREW TRUAX: Some nights it's been, like, really,

really intense, where it kind of has

a little, to me, I, has a little grind to it, as well.

SONYA MACKIE: It would be in the middle of the night.

You couldn't tell whether you're hearing it or,

or feeling it. It was a...

it was like a "vroom-vroom" noise.

TAYLOR: Imagine that you're sitting in a room trying to relax

and there's this low-level humming sound

in the background that you can just barely hear

and it's continuous.

So, if you have this constant acoustic hum in the background,

this could cause adverse reactions.

This hum is affecting people, keeping them awake.

It's-it's ruining their lives.

(low mechanical humming)

PROVOST: It does affect my sleep.

The pulsing and the pounding-- yeah, it, it wakes you up.

It just resonates through the house.

Sometimes it gets so bad

and you get so infuriated with it

that it scares

the hell out of you. You just want to get away.

Windsor being such a highly industrialized city,

we have a lot of different sources

of noise, but when it didn't go away.

that's when people started to get concerned.

SHATNER: For the residents of Windsor,

the hum is no longer a mere curiosity.

For them, it's become a full-fledged crisis.

One that the local authorities have tried to address.

CRAIG PEARSON: The Canadian government did a study.

And the report suggested that it came from Zug Island,

across the Detroit River in Michigan.

WHITEHEAD: And the conventional theory is that the U.S. steel factories

that are located on Zug Island are somehow causing

a weird reverberation effect that is carrying that sound,

uh, across the lake and people are hearing it.

MACKIE: When it first started, no one knew, uh, what the hum was.

They started studying it and that's where

the Zug Island theory came up.

But there's all these what-if questions that come up.

Why is it felt in the evening hours,

maybe versus more so during the daytime?

Why do you feel it on a weekend?

Are they actually running their facility on the weekend?

Why is it worse during...

when the weather patterns are different?

It definitely does pose

a lot of questions and a lot of what-ifs.

It could be many other places that generate this.

And low frequency sound could be due to

seismic activity.

In the Detroit area we know there's been an increase

in seismic activity.

One natural phenomenon that creates

low frequency noise is earthquakes.

In several cases, you can hear the earthquakes occurring.

They're very low frequency,

mostly below the human hearing range.

But in some cases, they can be heard.

Interestingly, some of the residents in Windsor

have noted the rattling of windows.

And, uh, I've experienced an earthquake

where I had no idea it occurred except

all the windows of my house started vibrating.

There was something in that resonance

of that earthquake that was

the same frequency as-as my windows.

NOORY: These hums are around on this planet in certain areas.

Uh, exactly what's causing it, nobody knows.

But it's very annoying to a lot of people.

Just imagine yourself trying to sleep,

feeling this hum all the time.

It drives you nuts.

MACKIE: It'd be nice if it would be explained.

Maybe one day.

It would be great if it went away.

It'd be nice not to hear it anymore.

So what do you think?

Could Earth be creating a disturbing hum?

Or is it the work of modern technology?

It's a perplexing question and suggests that the mysteries

of our planet are much greater

than we are currently capable of understanding.

So, as we seek to learn more about earthquakes

and volcanoes and even mysterious balls of light,

we may find that the strange forces of nature

are meant to remain unknown

and unexplained.

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