Science & Technology

Spacewalking: Training

Chris Hadfield

Lesson time 17:32 min

Chris describes his personal experience training for spacewalking in an underwater simulation and emphasizes the importance of gaining confidence in maneuvering and monitoring the spacesuit.

Chris Hadfield
Teaches Space Exploration
In 28+ lessons, the former commander of the International Space Station teaches you the science of space exploration and what the future holds.
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The very first spacewalk was done by a guy named Alexey Leonov. And he just about died. He went out on the spacewalk. His suit inflated. It was way stiffer than anybody expected. He couldn't bend his arms. He couldn't bend at the waist. The airlock that they had hastily constructed, because it was during the days of the space race, was actually made of pressurized material. So it was almost like coming out of one of those bouncy castles. And he was outside on a spacewalk. He was only out for one big pass of Russia, just 10 minutes or something outside. But when he tried to get back in, none of their preparation had gotten him ready for what it was actually going to be like. And he just barely got back in. In fact, Alexey, who was a really good gymnast and a very fit man, he had to manually depressurize his spacesuit right down to the level where it could barely keep him alive, where he was risking the nitrogen boiling out of his blood and getting the bends just to make his suit flexible enough that he could somehow physically manhandle his way back inside, pull the airlock in, get the hatch closed, and accomplish our first spacewalk. We learned a lot from Alexey. And we also learned that we need to somehow prepare and simulate for spacewalking in a much more realistic manner than he did. And we thought, what's the most spacewalk-type environment that we have on Earth? It's underwater. It's like scuba diving. And so the very first American astronauts that were going to spacewalk, they actually went down to some of the Caribbean islands. So they had a lucky break to do their spacewalk training in the shallow water using some of the early scuba equipment to try and train and develop spacewalking techniques. But then they dug an underwater training facility at the Johnson Space Center in Houston, Texas. And ever since then, ever since Alexey first took a huge risk to try and figure it out, we've been training for spacewalks underwater. We build an entire piece of space hardware down there. In the early days, it was the Space Shuttle, because that's where all our spacewalks occurred from. But now there's a huge section of the International Space Station permanently underwater in one of the biggest swimming pools in the world just on the outskirts of Ellington Field by the Johnson Space Center. And that's where I spent hundreds and hundreds of hours underwater, days and days underwater, trying to learn how to operate a spacesuit, how to maneuver myself, how to think in three dimensions, but also how to invent spacewalking, how to develop all of the techniques. It's not so much like you're just going to class and learning how to do something. It's not like you just go to astronaut school and you get a certificate and now you're qualified. It's more you have to gain all these skills, but then you're part of the team that is applying those skills, since it's all so new, to invent new techniques to do things, so that you and your crew...

Explore the unknown

Impossible things happen. At age nine, Chris Hadfield knew he wanted to go to space. He eventually went there three times, becoming a commander of the International Space Station. In his MasterClass, Chris teaches you what it takes to explore space and what the future holds for humans in the final frontier. Learn about the science of space travel, life as an astronaut, and how flying in space will forever change the way you think about living on Earth.


Students give MasterClass an average rating of 4.7 out of 5 stars.

3rd lesson here on Masterclass. By far the best. Though I'm a music composer, I do have a fascination for space and Chris speech was very eloquent and I appreciated the fact that he knew how to speak in lamen terms. This is the kind of knowledge we should be promoting in the world.

Love it when a very intelligent person can pass along his knowledge to anyone at any level. Gained a lot of knowledge on the space program and other concepts. We need more of these people!

So easy to listen to the stories and wonderfully accessible explanations of some fairly complex ideas. Enjoyed every bit of this class!

Great informative class.. Chris is an inspiration. Thank you!


Marc W.

Chris is an amazing guy. Quite accomplished. I'd have a beer with him. Sometime the lecture can seem a little preachy.


it was a great lesson! so many details and sadly it was sad to here that the astronaut that cris talked about had died

laura J.

How does each have enough energy to work toward working for hours and then expected to do the job, working, learning and testing. What happened after you were in the pool for hours, did they feel any muscle problems?

laura J.

I cannot open my pdf for the classes from Chris, maybe someone could advise as no problem with other instructors

Ugo A. D.

I really enjoyed this lesson and the context in which Chris describes the requirements for training for a spacewalk. Especially when he describes the part from exiting out of the airlock into the universe, you can almost sense his awe and appreciation for having the opportunity to see the universe up close. I wish I was his spacewalk partner. Good stuff.

Pedro C.

This theme is so challenging and inspiring. It left me wanting to get into a Spacesuit and assume the challenges!!! It would have been so nice to get access to videos of complete sessions of training, just to get the "experience". Also, it would be great to watch real incidents and accidents during spacewalking, discussed from a training perspective.

Myroslav R.

Could someone explain me - the inertia works differently on orbit and under water, how does the astronauts train work in such condition?


Fascinating! The mental game behind all of this is just incredibly fascinating. The people who live this life, who create this training, who assist in these trainings, It's all poetry. I'm so glad I thought outside the box and tried this class. The personal growth I'm getting from this class is just enormous. I can't thank you all enough. Especially Chris for sharing his huge wealth of knowledge.

Terry W.

I could also imagine Dr. Who's Tardis - opening the hatch is space would be like opening the Tardis and being somewhere completely different from you you entered. - from small confined space to infinity and beyond ;) The disorientation must be incredibly challenging. I like the problem-solving regarding communication in space - how to reference a point or a direction that is meaningful and precise relative to both astronauts, or space station occupant and space-walker. How can 2 astronauts facing 2 different directions agree on where something is relative to both points of reference? Communication - so precise, so planned - and we have trouble with texts and e-mails. I had to chuckle at the things that had to be worked out. :)

Marc S.

This is undoubtedly my favorite lesson so far. We've already heard Chris describe numerous complexities in basic terms that we can all understand. However, I laughed hard twice during this lesson. The first was when Chris compared (at a basic level) the feeling of opening the hatch to reveal the universe to opening your bathroom door to reveal Mt. Everest. At the moment he mentioned bathroom door, I thought to myself "this is going to be a poor comparison". I was so wrong. I laughed hard again when he said "putting a square astronaut into a round hole". I love this class.