Our bodies have physical limits.

Just squat down a little bit.

Come up and you'll feel out.

But when humans encounter abound, we tend to push.

How fast, How high?

How far two spacewalkers are currently 253 miles above the earth.

Exploration of our solar system is perhaps the most extreme bodily challenged.

Your motion sick.

You're uncomfortable.

You're disoriented.

That's because the human body is a complex network of bones, tissues and cells designed to suit our environment.

Here, Johnson Space Center Everything from food to spacesuits, toe exercise routines are designed so humans can survive in a world we simply aren't built for what happens to your body when you're in space.

Soon as you arrive in weightlessness, the fluid starts shifting in your body, your organs of balance in your inner ear immediately, since there's no gravity pulling down on him anymore.

All the joints and your muscles also sense that we know about these effects.

Because humans have been consistently living in space for over 15 years on board the International Space Station on, we're learning even more about how our bodies react in space.

After Scott Kelly became the first NASA astronaut to spend nearly a year on my S s.

As you spend more time in space, you lose muscle mass.

Your bones gradually lose calcium.

They gradually lose structural integrity because they're not fighting the force of gravity.

It sounds simple, but exercise is one of the most important activities for astronauts on board the S s.

They dedicate about two hours a day to it.

But this is not your average work out.

Okay?

Like this.

Hello?

Yeah, Okay.

That feels different.

When you were in space, can you describe the changes you noticed in your body?

More fluid will go towards the head, right?

And so you sometimes feel a little bit stuff here, like you've got allergies or something like that.

You can lose up to 2.5% of your bone density in a in a month in space.

This is very a very important part of counter acting.

But what about on a deep space mission?

If we ever get to Mars, do you think we'll have machines like this up?

They're keeping us fit.

Well, these machines take up quite a bit of space on board the International space station.

So I think if we go to Mars, there's gonna have to be something new.

Something probably a little bit smaller.

Little more compact something along the lines of ah rowing type machine.

NASA is currently testing a miniature exercise device on the I.

S s just as critical as exercise is what we put into our bodies.

Well, there.

In order to maintain their health and maintain top performing crew that are going to fulfill all their functions and have a very successful mission, we need to make sure that they're happy with the food system that they want to eat it the entire time.

Okay.

E say food is much better than I expected.

On a mission to Mars, the food needs to stay good for five years, a difficult challenge for food scientists.

So they're also working on growing nutrients in space like green peppers, tomatoes and lettuce.

But the point of travelling to deep space is not just to stay inside a spacecraft.

We want to go outside and really explore anywhere outside of Earth.

Really?

You need a space suit that has a lot functioning life support system because the pressure environment is such that your body can't survive.

Like around the space station.

Temperatures range from roughly negative 2 52 positive to 50 F.

That's a massive range.

Yes, it is in your body.

Wouldn't be very happy in the environment for a Martian environment.

NASA is currently working on their Z to prototype a spacewalking suit.

This is, I think it is.

It is what you think it is.

This is actually on adult diaper.

It's complicated enough to keep astronauts alive when missions are going as planned.

But what about when things go wrong?

What you guys are working on here, you could categorizes like worst case scenario.

Absolutely.

We are the survival method of last resort.

In many cases, the crew's survival engineering team works on emergency equipment like life rafts, breathing systems, protective suits, even the diapers astronauts would put on during a catastrophic event.

The urine will actually turn to ammonia over the matter of a couple of days, which is toxic to the crew.

Everything has to be considered because there's people's lives on the lives that's absolutely true.

We have never partaken in an effort to go to deep space with this many contingencies that we planned for.

Is this really gonna happen?

I certainly hope that it does.

I think that's why we're all here.