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CARL AZUZ: Hi, I'm Carl Azuz.
Thalassophile is a word you don't hear very often.
If you know what it means, and especially
if you happen to be one, you are going
to love this special edition of our show.
Simply put, a thalassophile is someone who loves the sea.
And the deep blue is where we're headed today,
specifically the deepest known part of the ocean.
Start in the Pacific.
If you can find the northern Mariana Islands
on the eastern part of the Philippine Sea,
you're only about 330 miles Northeast
of the Mariana Trench.
It's located 7 miles beneath the ocean's surface.
It's what National Geographic describes
as a scar in the Earth's crust.
This trench extends for more than 1,500 miles.
And it's 43 miles wide on average.
So this is a pretty big gouge on the ocean floor.
And if you go to the southern end of it,
you'll find its deepest point.
This remote place is called the Challenger Deep.
It takes patience to get there, even
after you sail right over it.
The submersibles that can withstand the pressure
take hours to dive this deep.
And even though thousands of people
have climbed to the top of Mount Everest, which
is 5 and 1/2 miles higher than sea level,
only a couple dozen have reached the 7 mile
depth of the Challenger Deep.
So it's largely unexplored.
But we know someone who has been there.
His name is Rob McCallum.
He's from New Zealand.
Last April, he and Australian Tim McDonald
became the first people from their countries
to dive this record depth.
They were kind enough to provide us with the video
you're about to see.
And I had the opportunity to interview Mr. McCallum
about the experience not long after he hit rock bottom
and then resurfaced in the spring of 2021.
So hold your breath and let's dive in.
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ROB MCCALLUM: It's the last unexplored frontier on Earth.
We know very little about this region, what we call
the hadal zone, which is that area of the ocean below 6,000
meters, or 20,000 feet.
CARL AZUZ: You can't just get there in a normal submarine.
What sort of vehicle does it take to withstand
the pressures there?
ROB MCCALLUM: That's a very interesting question.
Because pressure is entirely relative.
When a spacecraft goes up into space,
they're only experiencing a pressure change
of one atmosphere between the inside of the spacecraft
and the outside.
We are dealing with a pressure differential
of around 1,100 atmospheres.
So we dive in a titanium sphere, which is able to withstand
100,000 tons of pressure.
Just on the hatch through which we get into the submarine, just
the hatch alone has 2,200 tons, or around five
fully laden Boeing 747s pushing down on it.
CARL AZUZ: That's incredible.
I mean, somebody can't go out and buy that.
How does one acquire a vehicle like that?
ROB MCCALLUM: This vehicle was made for this specific purpose.
It was designed and built by Trident Submarines in Florida,
specifically to be able to voyage
down through 7 and 1/2 miles of water column
to get to the bottom.
And that's why it's got kind of an interesting shape.
It looks like a pillow that's on its side.
And that's so that it can drop down through the water
column very, very quickly.
CARL AZUZ: You said very quickly.
How long does it take to get to that depth?
ROB MCCALLUM: It takes around 4 and 1/2 hours
to get to the deepest point of the world's ocean.
We go down through the water at about 6 feet per second.
CARL AZUZ: And coming back?
ROB MCCALLUM: We released ballast weight on the bottom
to spring us off the bottom and head for the surface.
And so it's about a 3 and 1/2 hour ride home.
CARL AZUZ: What are you seeing when you get to the ocean floor
in the deepest part of it?
ROB MCCALLUM: This is the most fantastic
part of what we're doing.
It's true exploration.
We never know what we're going to see.
Every dive has yielded something fascinating,
often something new to science.
We are seeing creatures for the first time.
We are discovering entire landscapes,
which were previously unknown.
CARL AZUZ: That's still a full day just in travel time.
So how much time does that give you on the ocean's floor?
ROB MCCALLUM: We try to stay down for three
to five hours on the bottom.
It's a big investment of time and energy.
It takes the entire team to get this vehicle prepared
and get it down.
And so we try to use every minute possible on the bottom.
Our submersible has three viewports,
one for each of the occupants, but also
one central one that allows us to see down to the sea floor.
We're also surrounded by very high
definition cameras that are all linked
to a screen in front of us.
And we can look in any direction outside.
And that's important because we don't
really know where we're going.
We're almost always the very first humans
that have ever been there.
And so although we have a three dimensional map that we've
made the day before, we need a very good view
outside to see what's coming.
For humans, we don't really fear what we can't sense.
And so when you're in an airliner
and you're looking out, you don't naturally
think of the wind going past at 500 miles an hour,
and it's minus 50 out there, and there's
not enough air to breathe.
You just-- look, I can see a town,
or I can see a track, or--
and the same in the sub.
There's no sensation of movement.
There's no sensation of sound.
You can't hear or feel anything from outside.
It's just a very peaceful, relaxing
cruise into the unknown.
I think that we know so little about the ocean
that we barely understand what questions
to ask, let alone have the ability
to understand the answers.
My role, and the role of the team that I work with,
is to simply open the door.
This is the first vehicle in all of human history
that has the ability to reach the deep ocean in any ocean,
at any depth, at any time.
It's akin to the Wright brothers with the first flying machine.
This is just the first baby steps.
CARL AZUZ: I know the technology might
be a way away from creating a sort
of ocean exploration station that
can withstand depths like that.
But we have reported on there is more
funding and investment in underwater exploration
stations.
I mean, how important would you feel
those would be as contrasted with, let's say,
the International Space Station?
ROB MCCALLUM: Both are important.
Don't get me wrong.
I'm not taking a shot at space travel.
But space is a vast void, a vacuum, that so
far has proved to be lifeless.
The ocean is nothing like that.
The ocean is full of life right from the surface all the way
down to the very, very bottom.
I think before we leave home and start exploring the heavens,
we should at least explore our own backyard more thoroughly.
I think that many of the answers to our collective future
are going to be found in the ocean, and some
of those in the deep ocean.
The answers to how we're going to handle all the carbon
in the atmosphere, the answers to the dynamics of our ocean
and how we can arrest the decline of the ocean,
but also the things that we might discover in terms
of valuable compounds for medicines and that sort
of thing.
CARL AZUZ: So why do you think there's so much interest
in space exploration when we could be exploring
what we have right here?
ROB MCCALLUM: I think it's as simple
as when we gaze up at the heavens,
we have a sense of wonder.
What's out there?
What can we find?
We always look skyward because we're terrestrial mammals.
We loop up to the heavens.
When we look into the water, we don't really see that much.
We see an opaque plant plain, a platform that we can pull fish
out of, maybe go for a swim in.
But we don't actually go too far down.
My dive was about 36,000 feet.
Most humans never get below about 300 feet.
So there's a long way to go yet.
CARL AZUZ: 10 second trivia.
What is the most abundant fish in the world,
herring, bristlemouth, minnow, or sunfish?
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Scientists believe the most numerous fish in the world
are bristlemouths or light fishes.
That's our catch of the day.
It is surely fun to take a deep dive into such
a "marine-teresting" topic.
There are oceans of possibilities, sights to see,
facts in the swim beneath the surface, schools of thought.
I mean, what better way to get a "gyre" education
than to immerse yourself in a current event?
Today's shoutout goes out to Grenada High School located
in Grenada, Mississippi.
There is one place we look for the schools we mention.
It's our YouTube channel at youtube.com/cnn10.
So please subscribe and leave your comment on our most
recent show right there.
That's all for our show today.
I'm Carl Azuz.
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