[indistinct radio chatter]
[narrator] Above the Atlantic Ocean...
And my first thought was, "What was that?"
[narrator] ...there is a region of space...
- I'd do this, and there'd be blood on my finger. - ...that is dangerous
for reasons we don't yet understand.
It's not clear why, but the last time there was communication
with the satellite, was actually in this area.
This area of the South Atlantic
was giving us errors all the time, every day,
every time we passed through it.
You can see there are some irregularities.
You see six or seven of these peaks each day.
[narrator] Some scientists now think the long-term effects of this danger zone,
may be far wider reaching than anyone ever expected.
On Earth, that can lead to a breakdown of the ozone layer.
[man] Our whole species has developed
under that kind of protective envelope.
[narrator] It's called the South Atlantic Anomaly.
And it may even have implications for the future of humanity
in space, and on Earth.
Deep within NASA's mission control center,
as small team of scientists works 24-7,
to protect NASA's astronauts from the dangers of space.
- You ready to write the alert? - [woman] Yeah, I'll get it set,
- so when we hit it, we can just send it out. - Okay, sounds good.
[man] Three-five. We are ready to start.
Two... one... booster ignition
and lift off of Shuttle Endeavor,
with NASA's final space station crew compartment
that brings a bay window view for our celestial backyard.
[narrator] For former fighter pilot, Terry Virts,
this was his first mission into space.
[Terry Virts] One of the most special experiences of my life
was seeing Earth for the first time.
As I launched at night time
I had a chance, very briefly, for a few seconds,
to see the whole east coast of America.
It kinda took my breath away. I wasn't prepared for that emotional impact.
[narrator] Terry was one of six astronauts on a 14-day mission
to finish constructing the International Space Station.
[Virts] By our fifth day in space, we were docked with the space station.
We were about 400 kilometers in altitude above the Earth.
It was a normal day.
[narrator] It may have been a normal day for someone
trained to work miles above Earth's surface.
But what happened next, changed Terry's life forever.
I was exhausted, like I was every night, getting ready for bed.
I got in my sleeping bag, pulled it over my head,
closed my eyes. And just a few minutes after that,
I saw this giant, white flash,
and I opened my eyes.
And my first thought was, "What was that?"
Computers were fine.
There was no problem on board.
None of my other crew mates woke up and said, "Hey, did you see that?"
It was just me.
And then it wasn't long after that,
a few days after that that I started noticing my face was bleeding.
I'd do this, and there would be blood on my finger.
There's a lot of mystery in space.
There's a lot of things that we don't know.
[narrator] Terry had just crossed into a region scientists call
the South Atlantic Anomaly,
the so-called Bermuda Triangle of space.
It's an area of heightened radiation
which experts have been aware of since the dawn of the space age.
But it's true danger only really became appreciated in the early 1980s.
In Surrey, England, a small team of university students
dreamt of joining the space race.
[man] Back in 1983, it all began.
And we did photographically record the building of the space craft.
This is state-of-the-art technology, 1980s style.
Absolutely nothing by modern standards, but remarkable at the time.
[narrator] These engineers wanted to build a communication satellite
using a low-budget, off-the-shelf technology,
the type of devices that had never before been sent into space.
In the mid '80s, everyone thought we were crazy to do this.
The, sort of, mainstream industry say, "Why are you doing this?
This is kind of like a toy space craft."
Because most space craft use special electronics to work in space.
[narrator] Craig's mission was a big risk at the time.
It carried some very early experiments in digital communications
and digital imaging. In fact, it was a pioneer of these techniques.
We were flying state-of-the-art technology
similar to the emerging personal computer technology of the time,
devices that essentially have an unknown heritage in space.
So part of the activity was to see exactly how do these things respond.
[narrator] The experiment so intrigued NASA,
that they agreed to launch the satellite.
[announcer] We have ignition, and we have lift-off.
[Craig] When we launched the satellite, we got data back.
It's always exciting, the first time you hear your space craft.
[narrator] The jury-rigged satellite had one unique and crucial feature,
designed to address any technological malfunctions.
[Craig] We had what we call error detection and correction coding systems.
So if there were any errors in the computer caused by radiation damage,
these would be detected and automatically corrected.
What we realized then, is we had a unique resource.
[narrator] Each error message clearly recorded
the exact position of the satellite when the failure occurred.
The chips we were flying turned out to be
quite sensitive to this radiation,
so we were getting a large number of errors.
One thing I did was started to map out where these errors were occurring.
And that gave me a view of the errors from the perspective of a map.
That really then, in a very concrete way,
showed you exactly what was going on.
And to my surprise, really, we got an awful lot of errors,
just off the coast of Brazil, in a region of the South Atlantic.
This area of the South Atlantic
was giving us errors all the time,
every day, every time we passed through it.
[narrator] Although unintentionally, Craig had helped create
the most accurate map of the South Atlantic Anomaly to date.
This was priceless information.
It confirmed the radiation hot spot could damage modern electronics.
From then on, anything that passed through this radiation hot spot
had to be capable of surviving it.
[narrator] Dr. Jurgen Matzka is a world expert,
who studies the South Atlantic Anomaly
After discovering just how damaging the Anomaly can be
to modern electronics, big space agencies around the globe,
began to notice the same phenomenon.
[Dr. Matzka] We have the space telescope, Hubble,
that has very delicate instruments on board.
And actually when this Hubble space telescope is flying
through the region, in the South Atlantic,
NASA could see that there were problems with these instruments.
[narrator] Today, Hubble's most vulnerable electronics are preemptively shut down,
while the telescope passes through the Anomaly.
[woman] Liftoff!
[Dr. Matzka] Very recently, there was the Hitomi.
The Hitomi was a satellite that got lost.
It's not clear why, but the last time there was communication
with the satellite was actually in this area.
Also, all space agencies have taken notice of this.
And, for example, the International Space Station,
when it is traveling in this region,
it's taking certain precautious steps.
[narrator] Space walks must be carefully planned,
whenever the International Space Station
enters the South Atlantic Anomaly,
So again, we have here obviously a problem in this area.
So all these events, and research over the years,
shows that there is something special about this region.
This cannot be a coincidence, so there must be a good reason for this happening.
[narrator] So what is causing the South Atlantic Anomaly,
and is there anything anyone can do about it?
[narrator] As society becomes more technologically-advanced
and humans strive to reach beyond our planet,
it's more important than ever to understand the dangers that lurk in space.
Here in Boulder, Colorado, a highly-specialized team
works to ensure the safety of both humans and hardware,
beyond Earth's surface.
The whole business of understanding the space environment,
and anticipating what's going to happen
is really a crucial one for our advanced technological society.
[narrator] The radiation above the Earth is driven
by the changing activity of our Sun.
Dan and his team look for solar flares,
super-energized radiation particles,
that are released from the sun, and stream towards Earth.
[Dan] Energetic particles from the sun
can probably be thought of, somewhat accurately,
as tiny, but very powerful bullets
that are being generated by the energy in the sun.
Those powerful bullets, if they were to strike a spacecraft,
they could cause damage within the spacecraft,
or within the electronics of a spacecraft.
[narrator] But in fact, the Earth is incredibly well-protected
from these solar bullets by its remarkable magnetic field.
We have this wonderful, protective umbrella above us.
The Earth's magnetic field prevents much of the powerful energy from the sun.
[narrator] This magnetic forcefield shields the Earth in two ways.
It deflects some of the dangerous particles back into outer space,
but it also traps some radiation,
holding it in a layer that is just miles above the Earth's surface.
So we have both the fact that the Earth's magnetic field,
in a sense, prevents radiation
from getting very close to the Earth,
but it also provides a trap for particles to be embedded
within the magnetic field for long periods of time.
[narrator] Beneath this dangerous blanket of trapped radiation,
the International Space Station,
and many of our key satellites,
fly in what is called the low-Earth orbit.
But this safe zone
doesn't always provide the protection that scientists expect.
[narrator] That means any astronauts passing through this zone
need to be monitored, and that's the job of Kerry Lee and his team.
[Dr. Kerry Lee] We're in the multi-purpose support room,
which is a back room in mission control at the Johnson Space Center.
And our goal here
is to keep the astronauts protected from space radiation.
[narrator] On board the space station,
live radiation data is beamed back to Kerry,
and reveals what happens when the International Space Station
flies over the South Atlantic.
You can see there are some irregularities that happen
at various places within the lower orbit.
We see six or seven of these peaks each day.
[narrator] These peaks in radiation occur each time the space station
passes through the South Atlantic Anomaly.
When the International Space Station passes through this intense region,
over here, you can see individual frames,
and the intensity increases where you have more hits in the detector.
[narrator] Over the South Atlantic, the trapped radiation
that should be held safely above the Earth,
dips down into the low-Earth orbit,
creating this radiation hot spot,
the South Atlantic Anomaly,
much closer to Earth than expected.
[Dr. Lee] This is the highest levels of radiation
that we see regularly in low-Earth orbit,
and it constitutes about 50% of the dose that the crew members receive.
[narrator] Passing through this zone can be potentially hazardous.
[Virts] I had heard about the South Atlantic Anomaly.
But until I was in space, I never really understood
just how important that place is.
[narrator] While on board the International Space Station,
Terry passed through the radiation hot spot several times a day.
The eye flashes he experienced were, in fact, radiation particles
flying through space, and impacting the back of his eye.
If one particle of radiation is hitting my optic nerve,
then there's a thousand others hitting all the other parts of my body
When I got back from space after my first flight,
I had noticed that my skin had started to bleed while I was in space,
and got really rashy and puffy.
And I went to the dermatologist, and he did a biopsy
and said that you have skin cancer.
It really stood out to me that my whole life, I had gone without skin cancer.
And now, after two weeks in space flight, I got it immediately.
I assume there was some type of connection there.
[narrator] In theory, Terry's mission should have flown safely
beneath the layer of radiation held around the Earth.
Yet, he likely suffered enough exposure to contract skin cancer.
To look at this in more detail, Jurgen wanted to measure
the magnetic field strength directly in the Anomaly.
And what he discovered was striking.
[Dr. Matzka] So we started the observatory end of 2009,
and we can calculate for every month since then.
We can see that there's a steep decrease in magnetic field strength all the time.
[narrator] The Earth's magnetic field
has slowly weakened globally, in the last century.
But the weakening in the Anomaly was much greater than expected.
Globally, the magnetic field is decreasing by 5% every hundred years,
but in Tristan da Cunha, in the South Atlantic Anomaly,
the magnetic field is actually decreasing by 5% in 20 years.
So that's a five-times stronger decrease
than we know from the global picture.
[narrator] The exact reasons behind the weakness existing here are still unproven.
But like a dent in our protective shield,
the weak spot in the South Atlantic allows trapped radiation
to come down closer to Earth.
And even more disturbing, this danger zone is on the move,
and it's getting bigger.
So there is a worrying situation
We know for the last years that the Anomaly is growing,
and we can even see this here, comparing only three years.
So 2016 and 2019, we can already see that the Anomaly is growing.
[narrator] This concerning trend
may have profound consequences
for the future of space exploration.
...something engineers across the globe must anticipate and solve.
In Colorado, Dan Baker and his team
are planning to launch a new satellite into space,
to precisely predict changes in radiation environments.
[Baker] These instruments will look very precisely at the sun.
They'll detect when there are large disturbances
that may be precursors to strong space weather events at Earth.
We have to build these instruments with extreme care.
They have to be well shielded and well protected.
Among the things we do, is use very dense material,
such as this tungsten, for example, which can block the highest energy particles.
This little block of material takes a weight lifter, such as myself,
to be able to lift it.
We also build with using thick aluminum walls
in order to try to block as much of the radiation as possible.
[narrator] Every year, more and more technologically advanced space craft
are launched into orbit.
There are now plans to launch, literally,
thousands of more small satellites to operate in low-Earth orbit.
[narrator] They're not only smaller,
they must also carry a huge amount
of increasingly complex and delicate hardware.
[Baker] That means making the electronics more dense
making the number of instruments on a given platform larger,
making the sensitivity, effectively, to space radiation
substantially greater all the time.
[narrator] But one thing these small satellites cannot carry is excess weight.
[Baker] Every ounce that one launches into space costs money.
And with very small space craft, very light space craft,
you can't put as much shielding,
therefore you can't protect yourself
against space radiation as much.
And so this is a constant battle between the immutable laws of physics
and the realities of cost, and the efficiency of the space program.
[narrator] And with the Anomaly continuing to grow,
the hazards to this key machinery could spiral out of control.
As it flies in a high-polar orbit, it would be passing through
the South Atlantic Anomaly several times a day.
And if it's subject to very intense radiation in that region,
and it's getting, essentially, incapacitated by that radiation
multiple times per day, it's really not going to be doing the job
that you want it to do in space.
[narrator] With the dangers facing satellites escalating,
scientists have made finding a solution to space radiation
a top priority.
Many regard the space radiation problem
as the tallest pole in the tent, as they say,
the most challenging problem. How can we make systems safer, more viable
for humans to take these long adventures in space.
[narrator] Because it's not just satellites
and spacecraft that are affected
by the intense radiation of the South Atlantic Anomaly,
the deadly cosmic force also wreaks havoc on the human body.
[narrator] Located just walking distance
from NASA's mission control in Houston
is Frenchie's Italian Restaurant.
Frenchie's has been a popular lunch spot
for astronauts across the decades.
- Frenchie, what's going on. - [Frenchie speaking Italian]
- [in English] How are you? - [Terry speaking Italian]
[narrator] It's a place that serves as a nostalgic reminder to Terry.
Charlie Baldwin was our former NASA administrator.
One of the nicest guys you'll ever meet. Franklin Chang-Diaz,
he is one of the smartest human beings on the planet.
He's actually a nuclear physicist,
and he became an astronaut,
flew in space, I think seven times.
He flew a ridiculous number of times on the space shuttle.
Every picture you see here on the wall, space radiation has impacted.
Everybody here has flown in space, and they've all been irradiated
in ways that just don't happen down here on Earth.
[narrator] As our understanding of that radiation grows,
so does our urgency in finding a solution.
For the longer duration missions that NASA's doing,
that our international partners are doing,
we're going to have to address radiation,
especially as we go out beyond the earth's magnetic field,
or if things like the South Atlantic Anomaly grow,
and make it more dangerous in low-Earth orbit.
Radiation is a big threat, and it's the number one threat,
in my view, to humans flying in space.
[narrator] Around the corner from Frenchie's, Dr. Zarana Patel,
recreates these harmful space radiation environments in this facility at NASA.
And can see, exactly, the impact the radiation has on the human body.
[Dr. Patel] We are collecting blood samples from the astronauts
before, sometimes during,
and then after, their flight, and quantifying their DNA damage.
[narrator] The damage caused by just a single particle of radiation,
can be lethal to body cells
It is powered with enough velocity, and enough energy
to go straight through your DNA.
[narrator] As a particle hits our DNA,
it can rip apart the chromosomes, and change their structure.
If you have a hit on your DNA, the body can repair, or it can also mis-repair.
[narrator] Our body naturally repairs DNA damage,
but when the impact is severe, the repair mechanism can fail.
And it's this process that Zarana is most interested in.
We've chosen three different colors, the red, green, and yellow,
to highlight three different chromosomes.
And you can see here, a green that has mis-repaired with the red here.
[narrator] Individual chromosomes are colored with fluorescent dye,
showing any that incorrectly combine with themselves, or other chromosomes,
and this can lead to irreversible damage.
So, when you have mis-repair like this,
we won't know that it is repaired adequately,
and if it isn't, you will have long term impacts,
and eventually, cause initiation progression of cancer.
[narrator] Although a direct link with Terry's cancer can't be proven,
in just two weeks in space, he experienced around the same radiation levels
that most people in Houston receive in six years.
As the South Atlantic Anomaly grows, so will the radiation exposure to astronauts.
And with engineering yet to solve the problem,
could biology provide the key to keeping them safe?
[Dr. Lisa Nip] So what I am proposing may sound quite futuristic,
but this technology can really help human beings
in either space travel, or here on Earth.
[narrator] For Dr. Lisa Nip, if we are truly to address
the challenge of future space travel,
we must fundamentally revolutionize the way we think about it.
[Dr. Nip] If you look at where I am now,
you'll see that I'm fairly high up on the mountains.
And for a low-lying creature like me,
I will soon experience symptoms of hypoxia,
where I'll have a bit of a shortness of breath, and an accelerated heart rate.
Curiously, there are some humans who have actually adapted
to this kind of high-elevation environment.
[narrator] Humans all over the world adapt to challenging environments,
and these adaptations are passed down through generations.
[Dr. Nip] A lot of human beings,
who have lived in high altitude for a long time,
have inherited genetic changes that enable them to survive
for long periods of time, without feeling any kind of illness.
But the problem with evolution,
is that it takes many, many generations to happen,
and it may be the case that we don't have enough time to make these changes.
Because humans, for the most part, have evolved
in a pretty-shielded environment,
where our planet's atmosphere
was able to deflect a lot of the solar radiation,
and the cosmic rays that come from space,
we have never really needed to evolve a way to protect ourselves
from a lot of the space radiation
that astronauts would experience.
[narrator] Lisa's work involves studying animals
that live in extreme environments here on Earth,
to see how they have adapted and evolved.
So there are many regions of Earth where humans could not possibly survive
for any period of time.
But still, in these environments, there are species
that are able to tolerate these harsh environments,
and what we call them are extremophiles.
[narrator] These microscopic creatures have evolved
to survive in some of the most extreme environments imaginable.
And Lisa thinks they could hold the answer
to the puzzling problem of space radiation.
[narrator] Biologist Dr. Lisa Nip, studies animals
that have adapted to the most severe conditions on Earth,
known as extremophiles,
and how they might change the future of humans in space.
My studying these extremophiles,
and really trying to understand how they survive these harsh conditions,
we can better learn ways to protect ourselves in the future.
[narrator] And there's one of these extremophiles in particular
called deinococcus radiodurans,
that Lisa thinks could play a vital part in the future of space travel.
And you can see here that there are streaks
of this deinococcus radiodurans.
What is interesting about them
is that they have some cell surface proteins
that bind to an orange pigmented compound
that is able to give some anti-oxidant properties.
When these species are bombarded with radiation,
and it experiences shearing of its DNA,
it's able to use these anti-oxidant properties to make really rapid,
and clean repairs to any damage that it has experienced.
[narrator] Lisa's ambitious plan is to find the genes
responsible for these rapid repair mechanisms,
and incorporate them into human DNA.
By transferring this unique activity into astronaut body cells,
they could be better able to repair DNA damage,
making them, effectively, immune
from the potential cancer-causing radiation in space.
[Dr. Nip] If humans were able to perfect the ability to gene-edit,
we may be able to remove the costs
of building the more physical aspects of space travel,
like building protective shields or building aircraft.
And if we were able to localize this kind of tolerance within ourselves,
it may really accelerate the way
that we can travel into space in the future.
[narrator] Gene-hacking humans to make them suitable for space flight
could be centuries away. It may never happen.
But the problems the South Atlantic Anomaly are causing
aren't just going to affect astronauts now, or in the future,
some scientist think the problem, may one day,
affect the future of humanity, here on Earth.
It's beautiful, isn't it?
[narrator] These scientists think that the South Atlantic Anomaly
could signal something much more profound,
something that could affect our long-term future on Earth.
[narrator] As the Anomaly continues to grow,
and make its way east, towards Africa,
these ancient lands could hold the key
to predicting the Anomaly's future.
[John Tarduno] This is a project that really started about 20 years ago.
So we've been thinking about this for a long time.
Trying to understand the South Atlantic Anomaly,
really requires us to get data from the southern hemisphere
on a longer timescale.
[narrator] John Tarduno is a geophysicist.
He studies changes in our magnetic field, way back in time.
And in this parched South African wilderness,
he's formed a unique partnership
with archaeologists Tom Huffman and Mike Watkeys.
To understand the earth's magnetic field,
the team needs to look at where it's created.
In the center of the earth, there is a solid metal core.
This inner core is surrounded by a liquid iron outer core.
And it's the movement of this liquid iron,
that generates the magnetic field around us.
Because the iron outer core is fluid,
it can cause irregular changes in the strength of the magnetic field.
[Tarduno] We know that the field
has been decreasing for the last 160 years,
but we don't have much of a historical context for this.
So what we're trying to do, is look at the record of the field
back further in time, to provide context for this more recent change.
[narrator] John thinks there might be something happening
in the earth's core, beneath Africa,
driving these rapid changes in the field strength,
and the growth of the South Atlantic Anomaly.
What we're seeing in the field right now,
in terms of its very rapid drop, is alarming.
[man] Yeah. No, that's it. That's it. Okay.
[Tarduno] So that's really giving us hints
that there's something active going on in the core.
To lead about to this decrease.
[narrator] To prove this, John is on a hunt
for certain types of ancient rocks
that hold information about the earth's magnetic field here.
These materials can contain magnetic minerals,
particularly something called magnetite.
[narrator] What John wants to find are artifacts
that have gone through a very specific process.
They must be heated to over 1076 degrees Fahrenheit,
then rapidly cooled.
This process locks in the strength of the magnetic field
at that particular location, at that particular time.
This is exactly the same type of information
that is being recorded at a magnetic observatory.
It's just like this is a spot reading
of the magnetic field, back in time.
And we just need to find enough of these to string them together,
to get a magnetic history.
[narrator] And what John and the team can deduce about our past
from this geological data, may have a profound impact on our future.
[narrator] Geophysicist, John Tarduno
is leading a team of researchers in South Africa.
They hope to learn more about the root cause
of the South Atlantic Anomaly,
and how it may change in the future.
There's a special place for Iron Age studies,
that's the last 2,000 years, it's Black pre-history.
This is a special place because we can do what's called landscape archeology.
We have data from tree rings, we have data from the isotopic study of bones.
Then we know that the climate has gone up and down.
The climate alternated between not-so-good,
really good, not-so-good, etcetera.
And it so happens that there's a correlation between the increase in population,
by the number of sites of that time period,
with the higher rainfall periods, and so on.
[narrator] One of the tribes that migrated to this region regularly,
called the Bantu, had some interesting cultural practices,
that offered John a unique resource for his study.
[Tarduno] The Bantu were the first people
practicing agriculture in this area.
So they, of course, were very reliant on rainfall.
And in times of low rainfall, times of drought,
they had ritualistic burnings of the village.
[narrator] By burning their settlements during a drought,
the Bantu believed this would call on the rain gods,
and bring better weather.
These regular burnings have left a series of rock samples,
providing a historical timeline.
The fact that there were several migrations of Bantu into this area,
is ideal, together with this ritualistic burning,
because that actually created this time sequence.
[narrator] Today, John and his team have found
a new, undisturbed area of burning,
something that could give him crucial insight
into what's driving the Anomaly beneath Africa.
First, John takes GPS readings,
to locate the precise position of the ancient sample.
The key thing now...
...this place here. I wonder if we can get a...
[narrator] He then draws a line in the rock, to provide a reference.
Using compass readings, he specifically orientates the current magnetic field...
[speaking indistinctly]
...before taking the sample back to the lab to analyze its magnetic strength.
His results suggest that the drastic weakening
of the magnetic field above the Atlantic, occurring today,
is anything but a one-off event.
So what we have found is that the magnetic field,
particularly the magnetic field intensity
has dropped in the past, in this area.
In particular in this interval between around 1250 and 1350,
the field was dropping quite rapidly,
and even more rapidly than it is dropping right now.
So based on these data, we would tend to believe
that the South Atlantic Anomaly may be a recurrent feature
[narrator] With regular drops in the field here,
John thinks there's something in the earth's core, beneath Africa
that's driving the changes in the magnetic field today.
[Tarduno] The core mantle boundary underneath Africa is unusual.
It is unusually dense, unusually hot,
and stimulating the changes in the flow underneath Africa,
leading to all of these phenomena.
[narrator] John thinks the unusual geology of the mantle,
just above the outer core, beneath Africa,
could be causing the strange movements of molten iron here,
driving the recurrent drops in field strength over time.
And perhaps, even the origin of the Anomaly itself.
If what John predicts is true,
the growth of the Anomaly and rapid weakening of the field today,
could potentially be a sign of much more drastic changes,
something that could have impacts on all of us.
[narrator] In South Africa, a team of scientists is examining
how the earth's core could be changing the planet's magnetic field,
and how those changes could affect humans in the future.
[Tarduno] If we think about the potential for the South Atlantic Anomaly deepening,
and becoming more extensive, then the effects become more profound,
and can affect the entire globe.
If it becomes very large, it could then effect the global magnetic field
and stimulating a magnetic reversal.
[narrator] Pole reversal is something that has happened to the earth before,
and not just once.
[Tarduno] For the last 80 million years, for example,
we know there were hundreds of magnetic reversals.
These are extremely well-documented
in the geologic magnetic record that we have.
So we know there's going to be a magnetic reversal.
Predicting exactly when that reversal will occur is a very difficult thing.
[narrator] The last reversal was around 780,000 years ago.
But occurring over history almost every 300,000 years,
it's only a matter of time before it happens again.
During a magnetic reversal, the field intensity is going to drop
to very, very low values. It might be only 10 or 20%
of the present day magnetic field intensity.
[narrator] Humans, both on Earth and in orbit,
would be dangerously vulnerable to the effects of space radiation.
This lower magnetic shielding,
then allows the charged particles greater access to the atmosphere,
and can then start to cause chemical changes,
the creation of nitrogen oxide compounds that can break down the ozone.
[narrator] The ozone is a thin layer of our atmosphere,
which vitally protects us from the sun's UV radiation.
And a reduction in the ozone layer could leave us vulnerable.
It will then allow more radiation to penetrate
that could eventually lead to higher skin cancer rates
for those people living underneath these holes.
So if we move into a world where we're heading toward a magnetic reversal,
we can start to see global effects,
not just the effects today that we're seeing in space
that are limited just to the South Atlantic Anomaly.
[narrator] And with space exploration only ramping up,
this shift in our magnetic field
has implications for the future.
The die is cast, effectively, on how space
is going to play a role in our lives now.
There may be many surprises. There may be many changes.
But I think they're all gonna be in the form of more and more utilization of space
for human activity
[narrator] And to continue traveling along this path,
the fight to solve the problem of space radiation is more important than ever.
The biggest problem that we have going forward,
if we're ever going to go to Mars, is actually radiation.
Bone and muscle loss has been solved.
The space station has fixed that problem
But the radiation problem has not been fixed.
[Dr. Nip] If there were ever a situation in which humans have to experience
much larger doses of radiation,
either here on Earth, or out in space,
it will be the case that gene-editing may be one of the few ways
that is most effective and efficient
in order to protect our species,
and make sure that we survive.
[narrator] To prepare for this unknown future,
scientists must continue to track the changes
of the South Atlantic Anomaly,
the Bermuda Triangle of space.