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Science & Technology

The ISS: Experiments

Chris Hadfield

Lesson time 13:02 min

Chris outlines a few experiments currently running on the ISS and explains how astronauts learn to conduct experiments in space on behalf of scientists on Earth.

Chris Hadfield
Teaches Space Exploration
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 space station that's above our heads right now is like this big orbiting laboratory going 25 times the speed of sound. But it is covered in experiments. We have them on the inside. We have them bolted to the outside. There's like this book that's on the outside, like as if you took a briefcase and opened it up. And it's a whole bunch of materials to see how they do in the vacuum of space. There's even this super light gel that's out there. And what it's doing is collecting all the little super tiny grain of sand sized meteorites because we want to know, what's the universe made of? And so let's collect them in this aerogel. We've got sensors staring at the Earth on the outside. We've got telescopes staring at the universe. And on the inside, we have nanoparticle experiments. Because of course without gravity, things don't settle to the bottom. So we can study nanoparticles suspended in fluids. And if you make them reactive to an electric field or magnetic field, you can maybe change the fluid properties of a liquid by modifying, through an electric field, the orientation of the nanoparticles inside that fluid. You could then use that as a shock absorber underneath a building during an earthquake or in a car or something, potentially. And it's a place to study it without gravity. The space station is this is this great amalgam of experiments all jammed together. But there's a lot more experiments on earth than there is room in the racks on board the space station. And there's 15 different partners who have built the space station. So there's a constant battle of who can get their experiment up there. And we try and do it as logically and as efficiently as we can. What is the merit of this experiment? Why does it truly have to be in space? How highly do the really educated people in this field, the peers, how highly do they rank that experiment versus another? What sort of peer reviews does this experiment get versus other ones? And we try and map them altogether. Of course each country that's part of the space station has contributed some percentage of the cost of building it. So we apportion out rack space based on how much that country put into it to try and make it equable and fair. But it's a constant discussion. How much power is that experiment going to take? How much cooling does it need? Does it have waste gases? It's a big juggling match with almost an unlimited number of balls for the payloads in the experiment and the science teams on Earth. But up on the space station, the astronauts are just trying to make sure that all those experiments are working. We're the lab technicians. We're the lab rats. We're the repair team. We're the plumbers. We're the emergency-response team. We're just up there trying to be not just the brains but the hands and the eyes of all of those researchers all around the planet. At any given moment, there are hundreds of experiments running on the International Space Station. During...

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.

Amazing story. I didn't know that it was so hard to become an astronaut, but now I know :-)

Thank you, you gave us a great insight into the life of an astronaut. It help me understand the scale. Enjoy the journey not just the end goal. Best Masterclass.

This has been a fascinating and empowering journey. I honestly could not identify what component was better, the understandable version of high level topics, or the perspective gained by such an extraordinary human. Thank you Chris!!

Its great to share history with such an inspiring and heartwarming human being.


Bernardo F.

I remember that a couple of years ago, maybe 2015, children were invited to submit an experiment to be conducted in the ISS, it was fascinating reading all those ideas as they have so much innocence and really want to know more. I don't know who won, but surely it's given us precious information. Overall, the ISS is just helping us humans understand more not only about the outer space, but also about what are the deals if we want to go farther.

William D.

Radiation exposure is a concern. Chris only mentions high energy neutrons. However; that completely ignores exposure from gamma radiation which is also a concern. Beta & Alpha radiation are taken care of with simple clothing or structure. Shielding from neutron & gamma radiation is hideously massive. 2 inches of lead are required to reduce the exposure by just 1/10th.

Maddie W.

One of my favorite things as a student is hearing brilliant professionals talk on what they are passionate about. Chris Hadfield's energy, respect, and admiration for science is truly inspiring to witness. I wish more people had this kind of education so they, too could learn about all the amazing discoveries we are making up there among the stars. It always kind of frustrated my curiosity in astronomy and physics classes when professors would say that we have no idea how gravity works on an atomic level or we have no way to explain most of the matter in the universe or why its expansion is increasing. It was really cool to learn about how we are studying these ideas on the ISS and the possibility that one day, we might finally be able to answer these questions and even more that we haven't even thought of yet. A big thank you to Chris for emphasizing the importance of what astronauts do in space and why we should all be in awe of the things they have discovered. The universe is in good hands.


This is like one of my favorite classes. So much science!!! Keep it comin', keep it comin'!!!

Deborah S.

Can we make this required science for high schools? Imagine the young minds expanding and developing what our future in space might look like. We can't short change our future by not sharing this with the future Astronauts and NASA engineers.

A fellow student

What if we use superconductive magnets for creating a local magnetic babble for defence our ship from radiation? Space is quite cold place. If we organise protection against sun rays we, probably can use second generation of high temperature superconductors (REPCO)

Jerry R.

Neil Armstrong said that the radiation problem was the next big thing we have to solve before going into outer space. Wondering if some kind of magnetic shielding device is the answer. No clue as to how it might work.

A fellow student

What about using that gel as radiation shielding? Then, assuming it works, you can examine it at the end of the ships life/mission and learn stuff.

Pedro C.

It is great to see how diverse experiements are being carried out at the ISS.

stasia P.

I am overwhelmed with the passion for which you teach and explain things that I thought would be hard for me to understand. I wish you could come to my house and explain to me why I have been doing laundry for 4 people for the past 24 years of my marriage and have lost thousand of socks… explain that to me please.