It's actually NASA's

Exploration Extravehicular Mobility Unit,

or xEMU,

the first new flight spacesuit

developed by the agency in over 40 years.

And it's what the next astronauts will wear

when we finally go back to the moon in 2024.

But before its boots touch the lunar surface,

the suit must be tested, rigorously.

Amy Ross: We know that if we don't do our job well,

we can kill somebody.

Narrator: Testing isn't just about

making sure it functions.

It's about making sure the astronauts who use it

come back home safe.

Ross: We are a life-support system.

And so that is something that we all know

and keep in the back of our minds

every day as we do our job,

because rule No. 1 is crew members come home.

Narrator: This is Amy.

And Amy has to make sure the suit

can stand up to a lot.

The Artemis program plans to take crews

to the moon's south pole

for months at a time,

in shadowy regions that could drop

to minus 370 degrees Fahrenheit or even lower.

And astronauts will have to double as geologists,

especially given NASA's discovery

of the presence of ice on the moon,

something that could help fuel rockets,

turning the moon into a gas station en route to Mars.

So the xEMU testing process

has been long and grueling,

with some tests run twice the recommended amount

just to be safe.

It's all broken up into three phases.

Development,

design verification,

and qualification.

The first phase is all about finalizing a design.

Amy and her team try out

a bunch of different lower-quality components

before deciding which design to actually build.

Ross: You now, it's like a car.

Is your car's steering good?

Well, until you put it in a car,

it's hard to tell.

We can put different shoulders in and see,

does this shoulder work better than this shoulder?

Narrator: Once that's all figured out,

the suit moves to the design-verification stage.

Ross: The idea is that we're going to

stay on the moon for months at a time.

And that means that you need

to be very flexible and capable,

and you need to be durable.

Narrator: Now, we've been to the moon before,

but not for this long,

not this location,

and not with the knowledge we have now.

Ross: We're being asked to go to

permanently shadowed regions

because there are gases in those places

that stay very, very cold.

And I'm talking, like, minus-370-degrees-Fahrenheit cold.

Narrator: They won't be working

in temperatures that cold,

but the suit does have to withstand temperatures

as high as 250 degrees Fahrenheit

and as low as minus 250 degrees Fahrenheit,

a wider range than ever before.

To make sure it holds up,

NASA tests the suit in what's basically a big,

vacuum-sealed oven/freezer,

both manned and unmanned.

Ross: Chamber B here at Johnson Space Center

is a human-rated thermal vacuum chamber we'll use.

We'll go in there with a portable

life-support system on our back,

then we'll test the suit through

its different phases of operation

to make sure that it does hold up

and operates in the vacuum

and in the thermal environments that we'll see.

Narrator: Along with temperature controlled,

the suit must be durable.

When we first went to the moon,

scientists were concerned

that the regolith-covered lunar surface

wouldn't support the weight of people and machines.

But the real issue with the regolith

is that it's sharp and dusty,

something that could really muck up

the fine-tuned workings of a spacesuit.

So, where's the best place to test dust resistance?

Ross: In an environment that's dusty and rocky.

Narrator: This is what durability testing

in the Arizona desert looks like.

Ross: And that kind of tells you

what parts of your suit are affected by the dust,

does it have a problem with the dust so much?

Is your mobility system really able

to walk over this rough terrain?

Those kinds of things.

Narrator: But the desert simulates

the terrain of the moon

and not a lot else.

In order to test mobility in lunar gravity,

the engineers have to move someplace wetter.

Ross: Like the neutral buoyancy laboratory, our big pool.

Narrator: In this giant pool, 40 feet deep,

astronauts can see what it feels like

to be on the moon,

to a point.

Ross: It's not really like moon gravity,

because as you try to walk,

you're having to push through the water.

But as a reasonable analog to do some activities,

it's a good one.

Narrator: Activities like ladder climbing, using tools,

and ceremonially planting the American flag.

These tests let engineers collect objective data

about the suit's life-support system and mobility,

but also subjective data

about the crew's experience using it.

Ross: Our suit's not done until they say it's done

and they like it

and they think they can use it to do their job.

Narrator: Now, qualification testing

includes a lot of the same stuff as design verification,

but there are a few key differences.

Ross: Part of it is the paperwork.

Narrator: Things get a little more strict

in the qualification stage.

Ross: We have a lot of caretaking

to make sure that we understand

everything that is done with flight hardware.

You change a screw out,

there's a piece of paperwork,

it says this new screw got put in

on this date to this particular place.

Narrator: Since this is the stage

that lower-quality test hardware

gets swapped out for the fancy flight-ready stuff,

testing can slow down a bit.

But in the end...

Ross: When you do qualification testing,

you're really using that as a proof for everybody

to put in front of everybody

that says this suit is good to fly in space.

Narrator: And once they get the green light...

Ross: That's when you load it onto a vehicle,

take it up to space, and use it in a mission.

Narrator: NASA plans to send the xEMU

to use on the International Space Station in 2023

to collect flight data

and confirm the suit's overall performance.

It's important to note that

this isn't actually considered a test.

Ross: At NASA, we need to feel like

we're very confident that that hardware

is going to work the way it was required to work

before we fly it.

So we don't usually go into flight calling it a test.

Narrator: Instead, it's a flight-data mission.

And it will be one of the last major milestones

before the xEMU is ready to land on the moon.

Spacesuit testing can take years,

thousands of elbow bends,

and even more tests than we're able to show here.

But it's all necessary

to ensure the comfort, functionality,

and, most of all, safety for NASA's astronauts.

Oh, and I know you're probably curious

about how they test the suit's bathroom situation.

Well, NASA has basically created a diaper.

Ross: And we tend to use simulated urine,

just to keep things tidier.

Narrator: There you have it.

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