All language subtitles for The UnXplained S04E15 1080p WEB h264-KOGi_track3_[eng]

WILLIAM SHATNER:
Shadowy objects hiding
above our planet.

Unidentified vehicles
moving through outer space.

And a strange radio signal

that may have been sent
from another world.

For thousands of years,

humanity has looked
to the stars and wondered,

"Are we alone in the universe?"

Scientists have long theorized

the existence of life
among the stars,

despite the lack
of irrefutable evidence.

But as a new era
of space exploration begins,

are we on the verge
of finally proving

that extraterrestrials exist?

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

♪ ♪

At Ohio State University's

Big Ear telescope, which uses
a specialized antenna

to detect radio waves
from outer space,

astronomer Jerry Ehman

is poring over a printout
of incoming data

when he notices
something remarkable.

Buried amidst the random static

is a signal of such
extraordinary intensity

that he wrote a single word
in the margin beside it:

"Wow!"

JEFF COUGHLIN:
So the Wow! signal
just leapt off the charts.

It was so strong and so
unique that it didn't seem

to come from
any known human source.

JAMES BENFORD:
The exciting thing about
the Wow! signal was

it was in a frequency
band which is

forbidden to
broadcast in on Earth.

So it wouldn't be
an Earth signal.

But it looked just
like a transmission.

MICHIO KAKU:
When we detected
this Wow! signal,

it wasn't random.

It looked like it was planned.

So, people have theorized

maybe it was a message from
an alien civilization in space.

♪ ♪

SHATNER:
Many researchers
consider the Wow! signal

to be the strongest
evidence to date

of an extraterrestrial
radio transmission.

But almost 50 years
after it was detected,

the signal remains
shrouded in mystery,

in part because it has
never been observed again.

People have looked for the
Wow! signal to come back again,

but the unfortunate thing is
it just hasn't been repeated.

It's a complete unknown
whether we'll find

an intelligent civilization like

our own out there,

but that's one of
the reasons we're looking.

SHATNER:
The work that scientists do

to detect radio signals
from outer space

is referred to as the search

for extraterrestrial
intelligence, or SETI.

Since 1984, this research
has been overseen

by the SETI Institute,

which is located in
Mountain View, California.

SETH SHOSTAK:
At the SETI Institute,

all we do is we look at
the kinds of signals coming in,

if we pick up any, and see

if there's any
information in them.

Like the kind of signal
that you would expect

from an extraterrestrial
transmitter.

One of the most modern
radio telescopes we have

for detecting
extraterrestrial signals

is the Allen Telescope Array

operated by the SETI Institute.

So this is an array
of telescopes

that is specifically designed

to look for
radio signals from ET.

There have been dozens
and dozens and dozens

of SETI experiments.

We are curious about knowing

whether we're the only,
you know, only game in town.

SHATNER:
The work being done by the
SETI Institute is the latest

in a long line of scientific
efforts to determine

whether or not humanity

is the only intelligent
life in the universe.

KAKU:
Since time immemorial,
we have wondered,

"What's out there?"

Well, that paradigm
is with us today.

Today, we still wonder
what's in the stars.

It's sometimes said that
perhaps the greatest search

in the history of science
is to search for

how we fit in
with regards to the universe.

SHATNER:
For thousands of years,

astronomers could only
gaze up at the heavens

and wonder whether
there was life among the stars.

But the idea of actually
finding evidence

of extraterrestrial life
really took hold

in 1774, when astronomer
William Herschel

used new technology

to see other planets up close

for the first time
in human history.

ROD PYLE:
In the 18th century,
William Herschel comes along

and builds the largest
telescope of that time--

48 inches in diameter.

And he, in effect, invented
the field of stellar astronomy.

He's looking at the planets
and other nearby objects

and says, "Well, I think there's
people living on the Moon,

I think there's people
living on other worlds,

and I think there's people
living inside the Sun."

Herschel's influence
was significant.

The Founding Fathers
of the United States,

Thomas Paine, Ben Franklin
and Thomas Jefferson,

all read his work

and agreed with the potential
that there could be life

on other planets.

SHATNER:
As telescopes
became more powerful

in the late 19th century,

American astronomer
Percival Lowell

began to focus them on Mars.

And what he observed
on the Red Planet

was nothing short
of extraordinary.

PYLE:
Percival Lowell saw linear lines

going between the light
and dark areas of Mars.

And so he mapped
these meticulously

and he called them canals.

So suddenly, all this buzz
starts coming around

about "Wait a minute,

there are people on Mars
building canals?"

TEITEL:
This idea of canals
on Mars, that there was

an intelligent society building

this planet-wide system,
just gripped the world.

People were obsessed
with this idea

of the intelligent Martians
wanting to reach them.

There were plans to shine
a big light to Mars,

somehow signal to the Martians.

As Lowell's documenting
his Mars observations,

he starts writing
popular articles,

which are incredibly
widely read.

Now, it is notable that
this came out right about

the same time as H.G. Wells'
The War Of The Worlds,

which is a wonderful,

journalistically-styled
fiction novel

about the invasion
of Earth by Martians.

This is the time when the idea

of alien cultures
and extraterrestrials

really begins to flourish
and kind of explode.

SHATNER:
First published in 1897,

The War of the Worlds
popularized the notion

that humanity could,
in the near future,

encounter hostile beings
from another planet.

TEITEL:
War of the Worlds
started this whole trend

that we always think that aliens
are going to enslave humanity

or that they're going to see us
and somehow try to kill us all.

We have a lot of ideas
about what aliens could be,

and they tend to be
very violent images.

SHATNER:
By the early 20th century,
aliens had become a staple

of the imaginative works
of science fiction.

But in the 1940's,
eyewitnesses around the world

began to claim
that they had seen real

extraterrestrial spacecraft
flying in the sky.

Our history is full
of UFO reports

and sightings and abductions
and visitation experiences.

D'ANTONIO:
And in the last several decades,

people are looking up
and seeing UFO objects

that are moving
through our space.

The UFO phenomenon is real.

There have been consistently
a lot of reports

of unidentified objects.

Recently, there have been

classified briefings
in the U.S. Congress.

...on the UFO findings.

This is a matter of
great public interest

and has been for a very long
time to a lot of Americans.

Our government should not
hide the truth from us

for another second.

On June 25, 2021,

the Office of Director
of National Intelligence

delivered
a preliminary assessment

and what the media
and the public have seen

is a nine-page
unclassified summary.

But it essentially says
that this phenomenon is real.

This was a sensational headline.

the U.S. government
is saying, "Watch out!"

Historically,
the burden of proof

was on the true believers

to prove that these objects
are extraterrestrial.

And for the first time,
the burden of proof has shifted.

Of course, we can't be
definite about this,

but I would think that within
the next 50 to 100 years,

the probability that
we actually make contact

with an extraterrestrial
civilization

approaches 100%.

♪ ♪

It's thrilling to think that,

someday soon,
we might find proof

that there's intelligent
life in the universe.

But while scientists
continue to search deep space,

many believe there's evidence
to suggest that alien life forms

have already visited Earth.

SHATNER:
Inside the International
Space Station,

Russian cosmonaut Ivan Vagner

is recording a video
of the southern lights

when, suddenly,
his camera captures

what appears to be a formation
of unidentified spacecraft

above the Earth.

MERA:
It was an amazing
piece of footage.

These objects comes into frame,

which seems to be
of five lights,

and then suddenly disappear.

It happens quite fast
in the video.

One minute it's there,
the next one, it's gone.

SHATNER:
Vagner immediately posted
the video on Twitter,

and many people claimed
that the clip was evidence

of an extraterrestrial
spacecraft.

MERA:
The video is very interesting

because when
you look at the video,

it was speeded up.

It turns out that these lights

actually were visible by the
astronaut for about 50 seconds,

which is quite long.

So sometime later,

he comes back with
a second story saying,

"Maybe I misidentified them."

You know?

So we don't know
if really NASA leaned on

this astronaut to say,

"Look, you know, change
your story a little bit."

Or... that he genuinely
did think he made a mistake.

SHATNER:
A number of
mainstream scientists

quickly dismissed the lights
as misidentified satellites,

which would have seemed
to put the matter to rest,

except for the fact that
American astronaut Leroy Chiao

had a similar sighting
back in 2005.

LEROY CHIAO:
We were on a spacewalk

to install navigation antennas

outside of the
International Space Station.

We were in that transition
zone at part of the orbit

where we're going
from night to day,

and right at that moment,

I saw what looked like
five lights flying in formation

in kind of
an inverted checkmark.

There was no time

to take a picture of it.
It just happened

in just a couple of seconds.

Then we burst into sunrise
and everything was gone.

When I saw the lights,

I knew they were unusual,
but I really didn't assign

any, uh, big deal to them.

I just thought they were
a satellite constellation.

And I really didn't
give it any other thought.

And it wasn't till later
that we got these reports that

people reporting, were reporting
that I had spotted UFOs

and there was theories that

that might be
an alien spacecraft.

SHATNER:
Is it possible that the various

recent sightings
of strange phenomena

above Earth are evidence

that there is intelligent
life in the universe,

and that extraterrestrials

are secretly
monitoring our planet?

Many researchers claim that the
answer is yes because astronauts

are highly credible witnesses.

POPE:
When you look at the number of

sightings of UFOs
and anomalous phenomena

by astronauts,

the possibilities
are hugely exciting

because, generally, astronauts
are the sorts of people who,

as witnesses, are unimpeachable.

MERA:
Astronauts are absolutely

the best observers of
anything that's out there.

Their attention
to detail is incredible,

and they make absolutely
amazing observers.

So when we do get reports of
something strange being seen,

you can pretty much
take that to the bank

because they've kind of
looked at all the possible

rational explanations
and not come up with anything.

SHATNER:
The recent sightings

made by astronauts
are not the first time

that mysterious objects

have been encountered
above our planet.

In fact, there are similar
reports that date back

to the beginning
of the space age.

In 1965, during
the Gemini 4 mission,

astronaut Jim McDivitt

reported photographing
a mysterious object

outside his capsule.

Jim McDivitt was one of
the first astronauts to see

something unexplained in space.

He saw what looked like a
cylindrical spacecraft

or cylindrical object
with antennas sticking out.

He didn't know what it was.

MERA: He said it was
quite a large object,

and was moving quite
fast towards them,

He described it as
a shape of a can of beer,

with a prong sticking
out of one end.

And he had absolutely
no idea what this thing was.

So he grabs the nearest camera
and snaps it, but he's clever.

In case there's something
wrong with this one,

grabs a second camera
and takes another photograph.

And of course, he relays this
information back to, to NASA.

SHATNER:
Two days after
McDivitt's encounter,

the Gemini 4 Mission ended
and the crew returned to Earth.

The film from McDivitt's camera

was then processed
by NASA technicians.

But when McDivitt
reviewed the images,

he didn't see
a cylindrical object

with a large antenna
sticking out.

MERA:
James McDivitt was curious.

What the hell was up there
that was close to his craft?

So sometime later,

he's looking through
the images of this camera

and he can't find it.

All he can find is
some blue obscurity.

And he thinks to himself,

"Well, is it because
the camera was out of focus?"

So he grabs the images
of the second camera,

and he's looking
at those photographs.

And lo and behold,
it's not on there neither.

Just another obscurity.

POPE:
The photos didn't
come out really well.

So, what was it?
We still don't know.

Now, a lot of
people say, "Wait.

There was
a cover up about this."

That there was indeed
a genuine photo

buried in a vault somewhere
at NASA headquarters.

SHATNER:
Is it possible that NASA has
photographic evidence of a real

extraterrestrial spacecraft

that they've kept secret
for more than 50 years?

Perhaps.

But many researchers believe
that another orbital encounter

provides even stronger evidence

of an extraterrestrial
presence around our planet.

On the 155th day
of their mission

aboard the Soviet
space station Salyut 7,

Russian cosmonauts Oleg Atkov,

Leonid Kizim
and Vladimir Solovyov

witness an extraordinary event.

The Salyut 7 sighting
is one of the most

bizarre and
mysterious encounters

that we've had in space.

These Russian cosmonauts
are up there and suddenly,

they report that
the entire space station

is bathed in this
mysterious light.

It's this orangey glow.

And they look out

and they see strange
entities out in space.

POPE:
There are theories that
it was a hallucination

or something like that,
but, come on.

A shared hallucination where
everyone sees the same thing?

That's not very likely.

So it leaves you
with the impression

maybe this isn't
a hallucination.

Maybe this was real.

Are the numerous sightings by
astronauts of unusual phenomena

in outer space
simply misidentification?

Or are there forces at work
trying to keep the truth

about extraterrestrial life
hidden from the public?

Perhaps the answer lies

with a strange object
orbiting the Earth

which some people think
may be an alien satellite

spying on our planet.

SHATNER:
The Soviet Union
shocks the world

by successfully
launching Sputnik,

the first man-made satellite,
into outer space.

In the six decades

since that historic achievement,

more than 70 nations

have sent their own
satellites into orbit

around the Earth.

Today,

there are approximately 6,500
satellites circling our planet.

We send multiton satellites
into outer space all the time.

You can now communicate

with anyone, anywhere, anytime,

on the surface of the Earth

without a telecommunications
network on the ground.

Internet,

weather satellites,

reconnaissance--
all of it can be done

using the satellites
in outer space.

LAUNCH DIRECTOR:
Three, two, one,
zero and lift off.

SHATNER:
One unfortunate side effect

of launching so many
satellites into orbit

is the accumulation
of mechanical debris

left over from previous
space missions.

These objects
floating above our planet

are collectively referred to
as space junk.

Experts estimate that there are

128 million pieces of space junk

in orbit.

COUGHLIN:
Every launch we make,

we're putting out
particles and, honestly,

space trash into orbit
around the Earth.

So far, we've been able
to navigate around it.

But if we're not
careful in the future

and we put out
too much space junk,

it's gonna get harder and
harder to launch spacecraft.

SHATNER:
Scientists continue to monitor

the millions of objects
surrounding our planet.

But many researchers
believe that there is one

mysterious satellite
orbiting Earth

that was built not by man

but by an extraterrestrial
civilization.

On day nine of their mission

to construct the
International Space Station...

...the crew of Space
Shuttle Endeavor

is unpacking new hardware

when they spot
an irregular shadow

floating some distance away.

They quickly take photographs
of the oddly-shaped object,

but its dark color makes it
difficult to identify.

Almost as if it was
meant to be camouflaged

against the darkness of space.

TEITEL:
Astronauts took a picture

of some unidentified
object in space.

Once people saw that picture

they were convinced that
it was an alien spacecraft

or some kind of flying saucer.

But then that raises the
question of what it might be.

POPE:
This really was
something anomalous

because when you
think about satellites,

normally you think maybe
about something spherical

or about something

obviously manufactured.

But this is
all sorts of odd angles

and curved edges.

Like nothing the human mind

could conceive of
or design or build.

SHATNER:
After reviewing the photographs,

NASA claimed that
the mysterious object

was simply a thermal cover
that had broken free

from the space station
during construction.

But given the bizarre shape
of the mysterious object,

there are many people
who find that explanation

a little hard to believe.

Instead, they claim that
the images are evidence

of an extraterrestrial
craft in Earth's orbit

that is known as
the Black Knight satellite.

POPE:
The Black Knight satellite

is one of those
really curious mysteries.

And the theory is

that this thing is-is like a...

a sort of silent
sentinel in space.

And it's very difficult
to pin down how this started.

What's intriguing is nobody
really knows where the name

Black Knight satellite
came from.

We can't find
where the reference

suddenly came into
Black Knight.

But in 1954, one of the major
newspapers in the U.S.

released a story about

a gentleman known
as Donald Keyhoe,

and he was a very
well-known UFO investigator,

ex-military.

And he said
there is something up there

traversing the planet
Earth on an orbit,

and it's not built
by human hands.

SHATNER:
But if there really is a
satellite circling our planet,

built by
extraterrestrial beings,

then it naturally
begs the question,

what on Earth is it doing here?

The best wildlife documentaries

is when the animals
don't know you're there.

Well, if Earth is being
monitored, we're the animals.

So it is an
extremely logical step

to park a satellite in orbit

up there in space
just watching, recording,

harvesting information about us

and beaming information
and messages about us

back to the alien home world.

When we think about

the space program,
we are doing the same thing

with all the missions that
we're sending out to Mars,

with all the orbiters,

and even the probes at
the edge of the solar system.

SHATNER:
Has an extraterrestrial
civilization

sent a probe
to hover above Earth

in order to spy on us?

Perhaps.

But some scientists argue
that a better strategy

would be to observe our planet
from much further away

on distant asteroids

that are known as
co-orbital objects.

BENFORD:
A co-orbital object

looks like a distant satellite
of Earth like the Moon,

but much further away.

They were first discovered
about 20 years ago.

We know very little
about them as objects.

It's assumed they're asteroids.

We estimate that there are
several dozen of them at least,

and the nearest
co-orbital object is about

three million miles away.

So if extraterrestrial
intelligence

wanted to observe Earth
and not be seen,

the co-orbitals
are a fine way to do it,

because it will not
be so noticeable.

Could an extraterrestrial
satellite be secretly

monitoring our planet

as I speak?

For now, that question
remains unanswered.

But an even more
compelling mystery

can be found on
one of the moons of Mars,

where researchers claim
there is evidence

of alien technology.

SHATNER:
140 million miles from Earth,

after a perilous five-month
journey through space,

NASA's Perseverance rover
gently lands on the planet Mars.

A big part of our
interest in Mars

has always been
looking for life,

whether it's some kind of small
fossilized life in the rocks

or biochemical
signatures in the soil

that prove that there might
have been life on that planet

at one time in its history.

And people are getting
really excited,

because if we do find life

on another planet
in our own cosmic backyard,

that's a massive game changer.

SHATNER:
Ever since the NASA
spacecraft Mariner 4

made the first flyby
of Mars in 1964,

more than 40 additional
missions have been launched

to search the Red Planet

for signs of
extraterrestrial life.

But some researchers claim

that if Mars
is indeed harboring life,

we won't find it
on the planet itself.

Instead, they believe
there is evidence

of an extraterrestrial
intelligence

on a Martian moon
that is known as Phobos.

Phobos is just plain weird.

It's only about
seven miles in radius

which is, uh, very, very small.

And it's a really

bizarre and surreal
looking shape.

It's all sorts of odd angles--

a mixture of sharp
and curved edges.

A real jumble.

HAAS:
In the 1950s,

a Soviet Union astrophysicist,

Iosif Shklovsky,

noticed that Phobos
may not be a moon at all.

And he was approached by

Carl Sagan in the 1960s.

The two of them
worked on a book together,

Intelligent Life
in the Universe,

and in that book they both talk
about Phobos possibly being

an artificial structure.

TAYLOR:
In 1998,

the Mars Global Surveyor
took a picture of Phobos

that has this strange
three-dimensional cubic-looking

monolith structure on it.

And geologists have looked at it
and they can't quite explain it,

although they come up
with some theories.

But there's no real explanation
as to why it's there

and what its purpose is,
or how it was formed.

That's really intriguing.
What is it?

HAAS:
NASA scientists claim
that this monolith

is the result of a crumbled rock

that fell from
a nearby mountain ridge.

There's no such
surface feature in the area.

The surface of Phobos
is very smooth,

which was vindicated
in later images

taken by the Mars
Reconnaissance Orbiter.

It's very shiny,
very flat surface.

It's littered
with small craters,

and there's no surface
features sticking up.

There's no mountains,
there's no ridges,

and we have this weird obelisk
sticking out of the ground

which doesn't belong there.

D'ANTONIO:
In looking at
the monolith on Phobos,

we can't tell whether it's
a perfectly square object

or it's just
a rocky protuberance,

but it is seemingly out of place

on what looks like
the smooth surface of this moon.

That means
it might be artificial.

SHATNER:
Could the Phobos monolith really
be an artificial structure

built by extraterrestrials?

Some researchers think so,
and for further evidence,

they point to the fact that
Phobos is mysteriously hollow.

TEITEL:
The European Space Agency's
Mars Express mission in 2008

explored Mars' moon Phobos.

Using radar sounder technology,

it found that the moon
isn't actually solid.

There are large subterranean
voids in this body.

KAKU:
We have detailed photographs
of Phobos, and it turns out

that Phobos has
a slightly irregular orbit

that deviates from
Newton's laws of motion,

and this is because of the fact

that it's actually
a hollow moon.

So some people say, "Aha.

"Maybe it's a piece
of alien technology

in orbit around Mars."

POPE:
When you look at Phobos,

when you look at its
comparatively small size,

odd shape,

and apparent partial hollowness,

Phobos could be
not a natural satellite

but an artificial satellite,

perhaps put there by an
extraterrestrial civilization

to hide some sort
of monitoring device,

listening station,
whatever you call it.

SHATNER:
There are those who believe
that the best evidence

that Phobos is
an extraterrestrial outpost

was an incident
that occurred in 1989,

when a Soviet satellite
known as Phobos 2

was sent to investigate the moon

and it mysteriously vanished.

TAYLOR:
In 1989,

the Russians sent the Phobos 1
and 2 probes to Phobos.

And when it got there,

Phobos 2
took a couple of photos,

sent them back...

and then it quit working.

It disappeared.

We don't know
what happened to it.

But one of the images
is really strange.

There's a cigar-shaped thing
in the middle of the image.

And I find that
quite interesting

that a lot of the UFO sightings
are cigar-shaped objects.

Is that just a coincidence?
I don't know.

HAAS:
Some people speculate
that there's some type of

defensive mechanism on the moon

that was defending itself
against approaching spacecraft.

And when this probe approached
Phobos it was activated

and it destroyed the probe.

SHATNER:
Officially, the loss of Phobos 2

was blamed on a malfunction
of the onboard computer,

but the authorities never
came up with a good explanation

for the strange
cigar-shaped object.

And it makes you wonder--

was Phobos 2 actually shot down,

as some believe?

POPE:
If Phobos really is some sort
of extraterrestrial artifact,

is it something that's been put
there from a civilization

that's come from
much further away

as a sentinel?

We can't rule out
the possibility.

There's no getting away
from the fact that Phobos 2

was lost.

Is Phobos really an
artificial space station?

And if so, then where did the
aliens who built it come from?

Well, astronomers are using
a powerful telescope

that may reveal the answer
by showing us the home world

of an extraterrestrial
civilization.

SHATNER:
Astronomers from
the University of Geneva

announce an incredible discovery

in the pages
of the journal Nature.

They reveal that by analyzing
slight changes in the light

generated by the distant star
known as 51 Pegasi,

they were able to confirm
the existence of an exoplanet

around another star in our
galaxy for the very first time.

An exoplanet is just a planet

around somebody else's star.

It's not orbiting the Sun.

Before 1995,
we thought there might be

a lot of planets out there,
but we didn't know it.

And since then, there are
a lot of exoplanets

that have been found,
in fact, thousands of them.

That's a lot of planets.

KAKU:
Right now, we have catalogued
about 5,000 exoplanets

orbiting other stars,

and that's just
in our own vicinity

of the Milky Way galaxy.

And we have encyclopedias
documenting the size

and the characteristics
of these planets.

Every day, we discover
a new planet out there

that potentially
could carry life.

SHATNER:
Since it's true that our galaxy
is teeming with planets,

could some of them be home
to extraterrestrial life?

According to astronomers,
the answer is yes.

And they claim that these
planets can be found in

what is known
as the Goldilocks zone.

COUGHLIN:
In terms of the Goldilocks zone,

that's the right distance
from the star

where you're not too hot
and you're not too cold.

You're just right.

If you're on
the Goldilocks zone,

you can have liquid water
on your surface

without it freezing
or without it boiling off.

And where there's liquid water,
there could be life.

SHOSTAK:
Earth is obviously in the
Goldilocks zone for the Sun.

Those are the kind of planets
you want to find.

Because you probably
need water for life.

And thanks to telescopes,

we know that every
second or third star

has at least one planet

more or less
the same size as our own

in the Goldilocks zone.

SHATNER:
Will we ever be able
to prove that planets

located in the Goldilocks zone

are in fact home
to other life forms?

Well, some scientists believe
that we may soon find out.

Today is a historic day.

SHATNER:
At an event at the White House,

President Joe Biden
unveils the first image

taken by NASA's
James Webb space telescope.

JOE BIDEN:
It's a new window into
the history of our universe.

We can see light
from the oldest galaxies.

The oldest documented light
in the history of the universe,

from over 13 billion years ago.

SHATNER:
The ten billion dollar
instrument

is armed with the most powerful

infrared imaging technology
ever created.

And what's even more remarkable
is that the telescope

was specifically designed
to analyze planets that lie

in the Goldilocks zone
for evidence of life.

SHOSTAK:
The James Webb Telescope--

it's an infrared telescope,
so it's sensitive to heat.

But that's really not
the big deal.

The big deal is that
it can look, for example,

at a planet around another star
and actually see it.

It might only look like
a dot on a photo,

but you take the light
from that dot,

put it through a prism,
and you could tell

what's in the atmosphere
of that planet.

The James Webb Space Telescope
is like a magnifying glass.

It's gonna look
in extreme detail.

And the great thing is,
for the first time,

we can actually start to study

the atmospheres
of Earth-size planets.

If we look at a planet
and we can see chemicals

that we know don't occur
naturally in its atmosphere,

that's a really good indication

that they're produced
by industrial processes.

So if we see those
in an exoplanet,

that's a good sign that they're
produced by some alien industry.

It tells you there's very likely

an intelligent civilization
like our own

on that planet
producing those chemicals.

KAKU:
Given the fact that we have now
the Webb Telescope up there

giving us even more information,

given the fact that we
keep on cataloging more

and more exoplanets,

we are now flooded
with information about

potential lifeforms
in the galaxy,

perhaps even intelligent life.

And so this is a game changer.

The mere possibility that
the James Webb Telescope

might reveal life on other
planets is fascinating.

But if it's true,
as some believe,

that extraterrestrials exist
and have already visited Earth,

then how did they
cross the galaxy to get here?

Well, according
to some scientists,

it could be
by harnessing the power

of an entire star.

SHATNER:
Astronomer Tabetha Boyajian

and her colleagues
at Yale University

are combing through
data recorded by

the Kepler Space Telescope when
they notice something unusual.

They discover that a star

located approximately 1,500
light years from Earth

is behaving
in a rather strange manner.

Tabetha Boyajian, who was
working at Yale University,

was looking at some
nearby stars,

and she noticed that one star
had a big dip in brightness.

Not one percent
or a tenth of a percent

but 22%, which is enormous.

KAKU:
We call it Tabby's Star

after the person
who began to talk about this.

Stars do vary in intensity

because a planet
moves in front of it.

It maybe drops a half a percent,

but this is the first time in
history that we've seen a star

whose sunlight
diminished by 22%.

That's astounding.

What could be causing that?
We don't know.

But it's an ongoing mystery.

SHATNER:
Astronomers studying
Tabby's Star initially theorized

its dimming could be
the result of comet dust

passing in front
of its position.

But according to another theory,

the unusual dimming
could be caused

by a piece
of otherworldly technology

known as a Dyson sphere.

First proposed by physicist
Freeman Dyson in the 1960s,

a Dyson sphere
is a hypothetical device

that extraterrestrials could
be using to harness the energy

of an entire star.

If you're an alien civilization

and you want to get
lots of power,

you might build some really
large solar collectors in space.

So, one theory is that
there could be a civilization

that was maybe starting
to build a Dyson sphere

to harness the star's energy,

and it's blocking out light
as we see it from Earth.

SHOSTAK:
The idea that advanced societies

would collect energy
from their star

is so appealing
and so logical, really,

because with
the amount of energy

they could marshal this way,

they could build
a rocket propulsion system

that is so fast that they can go
from one star system to another

very close
to the speed of light.

SHATNER:
Is it possible
that extraterrestrials

could use the power
generated by a Dyson sphere

to travel across the galaxy
and visit other planets?

Perhaps even Earth?
It's an astonishing notion.

And further research
on this potential technology

may allow us to one day

finally get an answer
to the question of whether

we're alone in the universe.

COUGHLIN:
Our galaxy has hundreds
of billions of stars in it,

in addition to our own.

Nearly every one
of those stars has planets

like we have
in our own solar system.

And there are hundreds
of billions of galaxies

in the universe.

That means
there are just trillions

and quintillions of planets
out there in the universe.

It is nearly
statistically impossible

that we're
the only life out there.

So, what do you think?

Are we alone in the universe?

Or is there intelligent life
beyond our planet?

Just like our ancestors
before us,

we'll continue
to keep searching the stars

in hopes of answering
this profound question

that, for now, remains...

unexplained.

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