Science & Tech

Rockets: The Price of Exploration

Chris Hadfield

Lesson time 18:18 min

Rockets and spaceflight are dangerous by definition. Learn how astronauts manage their fears and cope with tragedy as Chris had to do after the loss of a friend in the Columbia Space Shuttle mission.

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

Topics include: Come to Peace With Risk and Learn From Tragedy • Turn Fear Into Motivation • Move Forward With Optimism


MAN: Challenger, go with throttle up. MAN 2: Roger, go with throttle up. MAN 3: This shuttle mission will launch-- My God. There has been an explosion. MAN 4: --2,900 feet per second, altitude nine nautical miles, down range distance 7 nautical miles. MAN 3: This is not standard. This is not something that is planned, of course. I can see a solid rocket booster has broken away from shuttle Challenger. That's what you're looking at in the middle of your screen. I cannot see the shuttle itself. I don't know if it's able to continue on one rocket booster. If it's able to jettison that rocket booster, it will be able to return to the Kennedy Space Center. Perhaps the shuttle engines are not enough to power the shuttle back down. By definition, rockets are dangerous. The real question is, can you make it safe enough and have you made your trade-offs good enough that you think you can trust it either to launch a robot or, in this case, to launch people? And on the space shuttle, it was pretty safe. I flew it twice. But it also killed two crews. We had two horrific accidents with this space shuttle. Both of them essentially caused by trade-offs of the rocket design. In Challenger in 1986, during launch, instead of all of this solid rocket fuel burning properly and coming out the back, you can look at this model and see that it's made of individual segments. They were shipped on rail cars from Promontory, Utah all the way down to Florida and assembled there. And because they're assembled down in Florida, there's just seals in there. And they launched on an extremely cold day. One of those seals failed, and instead of all of the hot explosion coming out the back, a little bit of it started leaking out the side and it cut the strut to the big external tank. And as soon as that strut got cut, the whole vehicle came apart and killed the crew on board. During the Columbia accident in 2003, a piece of the insulating foam of this external tank popped off, came down and hit the wing right here. We needed this insulating foam because the liquid oxygen and liquid hydrogen inside is so cold, we don't want ice to form on the tank and ice to hit the shuttle. But it's just foam. And every single flight, little bits of foam would come off. But in this case, a piece of foam about the size of a briefcase popped off, hit the left wing and knocked a great big hole in the front of the wing of Columbia. And so when it tried to come back into the atmosphere at the end of the flight, all of that heat of the friction and pressure from the atmosphere, instead of being taken up by the protective Thermo Shield of the shuttle, it got funneled down into the wing and it started melting all the internal structure of the wing. The left wing failed, the vehicle came apart and killed that crew. So there are trade-offs to building rockets. You try and make it as safe as you can, but it's never going to be super safe. MAN 1: All right, uh. Got a little problem on t...

About the Instructor

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.

Featured Masterclass Instructor

Chris Hadfield

The former commander of the International Space Station teaches you the science of space exploration and what the future holds.

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