How to Get to Space: Training for the International Space Station

By Laura Dattaro
Published: January 7, 2014

NASA astronaut Chris Cassidy is submerged in the training pool, called the Neutral Buoyancy Lab, to prepare for work on the exterior of the International Space Station. (NASA)

On Christmas Eve, two NASA astronauts ventured outside the International Space Station to replace a pump and fix the station’s ailing coolant system. Without it, the station’s electrical systems would overheat, constituting a major crisis for the ISS.

It’s exactly this kind of situation that astronauts train for before they depart for the station, Chris Cassidy, a NASA astronaut who returned from the ISS this past September, told It’s part of years of hard work that prepare the astronauts for both the routines and surprises that come with living and working in space.

“The most important thing we do is train for emergency situations,” Cassidy said.

And they train a lot. Cassidy has been an astronaut for 10 years and spent only six months of that time in space. The rest he spent on the ground, training for missions and providing support for the crews in space and their families. And it all starts with a phone call.

“So you’re doing your thing in the civilian world — and for me I was a military guy, I was in the Navy — and I got the phone call, ‘Do you wanna come to work at NASA?’” Cassidy said. “‘Oh yeah, absolutely, how fast can I be there?’ And then you show up.”

Houston, infamous receiver of problems, is where you show up, where new astronaut candidates move with their families. It’s home to the Johnson Space Center, which itself is home to two full-scale models of the ISS — one of which is at the bottom of a 20-foot pool that holds 6.2 million gallons of water.

But before new astronauts can get their hands on even a simulated space station, they spend a lot of time in classrooms, looking at Power Point slides and listening to instructors to learn about the fundamental workings of the space station and the rockets that take astronauts there.

“You’re starting out with baby steps,” Cassidy said. “‘This is a space shuttle. These are the wheels. These are the wings.’”

The space shuttles are not the rockets that get astronauts to space anymore, since NASA retired them in 2011; now American astronauts fly on Russian Soyuz rockets launched out of Kazakhstan. This means more Russian-language training and a lot more flying to Star City, Russia’s equivalent to Houston, an area of Moscow home to the Yuri Gagarin Cosmonaut Training Center, where Cassidy spent nearly every other month for a period of his training.

Tom Jones is seen with IMAX camera gear in the Zvezda service module of the ISS during a 2001 mission to work on construction of the station. (NASA)

Despite the transition to the Soyuz, the training for the station itself has largely remained the same as it was when Tom Jones flew up in 2001 to help build it. Jones, a former NASA astronaut, spent 53 days in space, for which he trained for seven years. In addition to the classroom training, the new astronauts spend a lot of time responding to simulated emergency situations, working with mission control and stand-ins for astronauts on the space station crew to make the simulations as realistic as possible.

“This was really world-class training,” Jones told “When it was all functioning with full complexity, with mission control, the shuttle crew and your instructor team all playing their roles, it was very impressive and almost a joy to be a part of — although they were making life miserable for you the whole time.”

One of the most difficult parts of training, Jones said, was working in the pool, known as the Neutral Buoyancy Lab. Being in that water is about the closest one can come to the feeling of being in space, making it the best place to practice long, complex spacewalks. But this meant Jones spent upwards of six hours at a time under water, sometimes hanging upside down by his feet, trying not to drop a tool while he connected cables and wires in a space station replica.

“I know there’s an up and there’s a down, but your brain gets so immersed in the complexities of the spacewalk that it’s very much all-consuming,” Jones said. “And so you ignore all the fake things around you and you pretend that you’re really there.”

Attired in training versions of the shuttle launch and entry garment, astronauts Mark Polansky (left) and Robert L. Curbeam participate in a simulation exercise in the motion-base shuttle mission simulator at the Johnson Space Center. (NASA)

During his first spacewalk, Jones experienced the need to prepare for emergencies firsthand when a hose in the coolant system sprung a leak and ammonia began to jet into space. “That was very scary,” Jones said, “because we were aware that if this coolant kept jetting overboard, we were going to lose the cooling system.” Jones’ spacewalking partner, Robert Curbeam, found the shutoff valve so the two astronauts could fix the problem without the pressure of an ongoing leak. The coolant leak had never been rehearsed, but was one of myriad potential problems discussed throughout the years of training. 

Even for astronauts without pending upcoming trips to the space, the ISS training comes in handy. For Cassidy, it’s back to life on the ground for at least a couple of years — working in support roles for other astronauts, improving his Russian and keeping up to date with his training.

“It’s a really huge part about our existence and our culture,” Cassidy said. “It truly is the most important part about going to space — being well prepared.”

MORE: International Space Station Celebrates 15th Anniversary

Many astronauts tweet from the space station, allowing the rest of us Earth-bound humans to get real-time glimpses of our planet from space. (NASA)

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