zipping down the Death Star.  We're in this very constrained area with Alvin, and on the

sides, we have walls, and on the bottom, it's all volcanic with tube worms. It's a totally

alien landscape. Earth's final frontier is the ocean floor. We couldn't survive there.

But life will find a way to fill any niche, and this environment is no exception. And

that's one of the reasons why scientists are pushing to explore this extreme environment...

before it's too late.

It's really important for us to get down there and try and understand,

at a base level, what's happening and what may be happening as humans impact that environment.

Which means this historic sub is getting an upgrade. Alvin is a deep-submergence vehicle.

It's a three-person machine designed to take people to some of the deepest places in the

ocean. It's a 57-year-old program that has stayed operational for those 57 years and

continues to make some pretty amazing discoveries. Every time Alvin dives, we learn something

new. One of the most exciting discoveries I think was made in 1977, with the discovery

of the hydrothermal vent systems. Just a few years ago, Alvin enabled

the discovery of this new deep coral environment. Because of these discoveries, Alvin is no

stranger to making headlines...

These first glimpses are only the beginning.

But it was Alvin's exploration of Titanic in 1986 that brought the sub worldwide attention.

And that has helped turn Alvin into a cultural icon.

Behold the Alvin, Pinky. Our ticket to the ocean depths.

For years, Alvin's max depth was

4,500 meters, giving scientists access to close to two thirds of the ocean floor. There's

always a sense of excitement and anticipation before getting in the sub, and that just comes

from the fact that you are likely to see something that no one else has seen before

and potentially make an important discovery.

Once you get in the water, you go from rocking and rolling on the surface of the ocean, and pretty

quickly, everything just calms down. And then there's this beautiful transition in color

as you go from kind of this light green color through these deep blues, all the way to black.

When we get to about 100 meters off the bottom, we turn the lights on, we make a very slow

approach, and we'll hover right off the bottom. When three people get in a submarine, what

happens is they become a single entity. And you become this three-brained, six-eyed, human

cyborg thing down there. I know that sounds crazy, but it's really the truth. You have

a lot of plans, a lot of samples that need to be collected. There's an intense level

of concentration and it goes by really quickly. It's really gratifying when you come off the

bottom. You've got a basket full of samples, not just for you, but for everyone, and you're

heading home having accomplished what you wanted to accomplish. But for scientists and

explorers, there's still much more to see—and the current model is reaching its limits.

It's been around for more than 50 years. And over that time period, it's gone through major

upgrades and overhauls. So about 30% of the upgrades happened just about eight years ago

and we're right at the end of stage two. So Alvin's now going to be able to go

all the way to 6,500 meters. We'll now be able to dive with Alvin to 98%

of the ocean floor. And so this opens up a whole area of the ocean that is not well studied

and not well explored. To find out what's down there, Alvin needed more than just a

simple facelift. All the principal systems have pretty much been changed—all high-tech

camera systems, the interface with all the science gear, control—a lot of really subtle

things that people won't even notice. Including the white material on Alvin's exterior.

That is syntactic foam. That is a material that's tiny hollow glass spheres embedded

in epoxy. This foam allows the 20 metric ton Alvin to achieve neutral buoyancy on the

seafloor. It helps keep the vessel in place, preventing it from sinking and rising when

it doesn't need to. However, getting to neutral buoyancy is only one part of the quest

to go deeper. The submersible needs to submerge. Woods Hole engineers outfitted Alvin with

new titanium ballast spheres, which regulate the air to water ratio in these tanks. So

adding a little bit more air into those spheres or flooding it with a little bit more water,

lets you kind of fine tune where you are. And in the deep submergence game, you'll

start to see lots of titanium in these vehicles, and for good reason. That's the titanium

sphere that the pilots and the scientists are inside of. It's a bit bigger. It's a bit

thicker. There's no reason not to stick with this metal that's really tried and true for

being extremely durable and resistant, not only to the pressure, but to the saltwater

environment that you're in. So with those additions, it's ready now to dive to 6,500 meters.

Pushing to extreme ocean depths will allow Alvin to reach the entire abyssal zone,

a famously unexplored region where few other crewed research subs can currently go. Even

the world's most advanced nuclear subs can't reach these depths. It's pitch dark, the

pressure will crush you, temperatures are near freezing, and it's filled with creatures

straight out of science fiction. So in the abyssal region, some things we want to look

at is, what is the biodiversity in this area? What is its role in the global carbon cycle?

What impacts have humans had already? We just don't really know. That's

because at the moment more than 80% of the ocean's depths are unmapped and unexplored. While

that leaves us with many unanswered questions, we do know that the ocean floor harbors a

potential future gold rush. There's obviously a connection with deep sea mining and what

that impact will have. There are iron manganese nodules that form in the

abyssal ocean. They're becoming increasingly important potentially as a source of rare

metals that allow us to build windmills and iPhones and electric car batteries. Already,

more than a dozen nations have begun exploring the Clarion-Clipperton Zone, a region in the

Pacific Ocean that is estimated to have more cobalt and nickel than anywhere on land. Because

of that, the earliest extractions could start as soon as 2024. We're in a unique position

to try and understand the environment that we're

potentially will disrupt if we extract those resources.

To understand how those ecosystems function. What happens if they're disrupted?

The only way to protect something is to understand it. And Alvin is one tool to do that. These

engineers are working through the vehicle's final preparations. We head out to Bermuda,

and we start our sea trials where we put the sub in the water progressively over a period

of about two and a half weeks and after these trials wrap up, Alvin will finally make its

debut in the Abyssal zone. The deep ocean has been ignored, not necessarily by will,

but by technology. And I'm really excited that we're going to have the ability to add

that piece of the planet to our understanding of the whole. Everything behind me is new

enough where it could easily last another 50 years. When we have a kind of unknown

in front of us, we want to explore it and I think it's the ocean's time.