I was the son of an aerospace engineer.

I lived and breathed the Apollo program.

We either saw the launches from our backyard

or we saw it by driving in the hour over to the Cape.

I was impressed by, obviously, space and everything about it,

but I was most impressed by the engineering that went into it.

Behind me you see an amazing view,

a picture that was taken from the International Space Station,

and it shows a portion of our planet

that's rarely seen and rarely studied

and almost never explored.

That place is called the stratosphere.

If you start on the planet and you go up and up and up,

it gets colder and colder and colder,

until you reach the beginning of the stratosphere,

and then an amazing thing happens.

It gets colder at a much slower rate, and then it starts warming up,

and then it gets warmer and warmer

until the point where you can almost survive without any protection,

about zero degrees,

and then you end up getting colder and colder,

and that's the top of the stratosphere.

It is one of the least accessible places on our planet.

Most often, when it's visited,

it's by astronauts who are blazing up at it

at probably several times the speed of sound,

and they get a few seconds on the way up,

and then they get this blazing ball of fire coming back in,

on the way back in.

But the question I asked is, is it possible to linger in the stratosphere?

Is it possible to experience the stratosphere?

Is it possible to explore the stratosphere?

I studied this using my favorite search engine

for quite a while, about a year,

and then I made a scary phone call.

It was a reference from a friend of mine to call Taber MacCallum

from Paragon Space Development Corporation,

and I asked him the question:

is it possible to build

a system to go into the stratosphere?

And he said it was.

And after a period of about three years, we proceeded to do just that.

And on October 24 of last year,

in this suit,

I started on the ground,

I went up in a balloon to 135,890 feet --

but who's counting?

(Laughter)

Came back to Earth at speeds of up to 822 miles an hour.

It was a four-minute and 27-second descent.

And when I got to 10,000 feet, I opened a parachute and I landed.

(Applause)

But this is really a science talk, and it's really an engineering talk,

and what was amazing to me about that experience

is that Taber said, yes, I think we can build a stratospheric suit,

and more than that, come down tomorrow

and let's talk to the team that formed the core of the group

that actually built it.

And they did something which I think is important,

which is they took the analogy of scuba diving.

So in scuba diving,

you have a self-contained system.

You have everything that you could ever need.

You have a scuba tank.

You have a wetsuit.

You have visibility.

And that scuba is exactly this system,

and we're going to launch it into the stratosphere.

Three years later, this is what we have.

We've got an amazing suit that was made by ILC Dover.

ILC Dover was the company that made all of the Apollo suits

and all of the extravehicular activity suits.

They had never sold a suit commercially,

only to the government,

but they sold one to me, which I am very grateful for.

Up here we have a parachute. This was all about safety.

Everyone on the team knew

that I have a wife and two small children --

10 and 15 --

and I wanted to come back safely.

So there's a main parachute and a reserve parachute,

and if I do nothing,

the reserve parachute is going to open because of an automatic opening device.

The suit itself can protect me from the cold.

This area in the front here has thermal protection.

It will actually heat water that will wrap around my body.

It has two redundant oxygen tanks.

Even if I was to get a quarter-inch hole in this suit,

which is extremely unlikely,

this system would still protect me from the low pressure of space.

The main advantage of this system is weight and complexity.

So the system weighs about 500 pounds,

and if you compare it to the other attempt recently to go up in the stratosphere,

they used a capsule.

And to do a capsule, there's an amazing amount of complexity that goes into it,

and it weighed about 3,000 pounds,

and to raise 3,000 pounds to an altitude of 135,000 feet,

which was my target altitude,

it would have taken a balloon that was 45 to 50 million cubic feet.

Because I only weighed 500 pounds in this system,

we could do it with a balloon that was five times smaller than that,

and that allowed us to use a launch system that was dramatically simpler

than what needs to be done for a much larger balloon.

So with that, I want to take you to Roswell, New Mexico, on October 24.

We had an amazing team that got up in the middle of the night.

And here's the suit.

Again, this is using the front loader that you'll see in a second,

and I want to play you a video of the actual launch.

Roswell's a great place to launch balloons,

but it's a fantastic place to land under a parachute,

especially when you're going to land 70 miles away from the place you started.

That's a helium truck in the background.

It's darkness.

I've already spent about an hour and a half pre-breathing.

And then here you see the suit going on.

It takes about an hour to get the suit on.

Astronauts get this really nice air-conditioned van

to go to the launch pad, but I got a front loader.

(Laughter)

You can see the top. You can see the balloon up there.

That's where the helium is.

This is Dave clearing the airspace with the FAA for 15 miles.

And there we go.

(Laughter)

That's me waving with my left hand.

The reason I'm waving with my left hand

is because on the right hand is the emergency cutaway.

(Laughter)

My team forbade me from using my right hand.

So the trip up is beautiful. It's kind of like Google Earth in reverse.

(Laughter)

It took two hours and seven minutes to go up,

and it was the most peaceful two hours and seven minutes.

I was mostly trying to relax.

My heart rate was very low

and I was trying not to use very much oxygen.

You can see how the fields in the background

are relatively big at this point,

and you can see me going up and up.

It's interesting here, because if you look,

I'm right over the airport, and I'm probably at 50,000 feet,

but immediately I'm about to go into a stratospheric wind

of over 120 miles an hour.

This is my flight director telling me that I had just gone higher

than anybody else had ever gone in a balloon,

and I was about 4,000 feet from release.

This is what it looks like.

You can see the darkness of space, the curvature of the Earth,

the fragile planet below.

I'm practicing my emergency procedures mentally right now.

If anything goes wrong, I want to be ready.

And the main thing that I want to do here

is to have a release and fall and stay completely stable.

(Video) Ground control. Everyone ready?

Five. Four. Three. Two. One.

Alan Eustace: There's the balloon going by, fully inflated at this point.

And there you can see a drogue parachute, which I'll demonstrate in just a second,

because that's really important.

There's the balloon going by a second time.

Right now, I'm about at the speed of sound.

There's nothing for me to tell it's the speed of sound,

and very soon I will actually be as fast as I ever get,

822 miles an hour.

(Video) Ground control: We lost the data.

AE: So now I'm down low right now

and you can basically see the parachute come out right there.

At this point, I'm very happy that there's a parachute out.

I thought I was the only one happy,

but it turns out mission control was really happy as well.

The really nice thing about this is the moment I opened --

I had a close of friend of mine, Blikkies, my parachute guy.

He flew in another airplane, and he actually jumped out

and landed right next to me.

He was my wingman on the descent.

This is my landing, but it's probably more properly called a crash.

(Laughter)

I hate to admit it, but this wasn't even close to my worst landing.

(Laughter)

(Applause)

(Video) Man: How are you doing?

AE: Hi there!

Yay.

(Laughter)

So I want to tell you one thing

that you might not have seen in that video,

but one of the most critical parts of the entire thing was the release

and what happens right after you release.

And what we tried to do was use something called a drogue parachute,

and a drogue parachute was there to stabilize me.

And I'll show you one of those right now.

If any of you have ever gone tandem skydiving,

you probably used one of these.

But the problem with one of these things

is right when you release, you're in zero gravity.

So it's very easy for this to just turn right around you.

And before you know it, you can be tangled up or spinning,

or you can release this drogue late,

in which case what happens is you're going down at 800 miles an hour,

and this thing is going to destroy itself

and not be very useful.

But the guys at United Parachute Technologies came up with this idea,

and it was a roll that looks like that,

but watch what happens when I pull it out.

It's forming a pipe.

This pipe is so solid

that you can take this drogue parachute and wrap it around,

and there's no way it will ever tangle with you.

And that prevented a very serious potential problem.

So nothing is possible without an amazing team of people.

The core of this was about 20 people

that worked on this for the three years,

and they were incredible.

People asked me what the best part of this whole thing was,

and it was a chance to work with the best experts

in meteorology and ballooning and parachute technology

and environmental systems and high altitude medicine.

It was fantastic. It's an engineer's dream to work with that group of people.

And I also at the same time wanted to thank my friends at Google,

both for supporting me during this effort

and also covering for me in the times that I was away.

But there's one other group I wanted to thank, and that's my family.

Yay.

(Applause)

I would constantly give them speeches about the safety of technology,

and they weren't hearing any of it.

It was super hard on them,

and the only reason that my wife put up with it

was because I came back incredibly happy after each of the 250 tests,

and she didn't want to take that away from me.

So I want to close with a story.

My daughter Katelyn, my 15-year-old, she and I were in the car,

and we were driving down the road, and she was sitting there,

and she had this idea, and she goes, "Dad, I've got this idea."

And so I listened to her idea and I said, "Katelyn, that's impossible."