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Astronaut Ricky Arnold trains in a NASA pool. NASA

Life can be very unpredictable unpredictable CHRISTOPHER BERNARD—E+/GETTY IMAGES not able to be predicted (adjective) The school snack choice is always unpredictable. for astronauts living and working on the International Space Station (ISS). There is no gravity. Parts of the station might stop working at any time. Space objects come flying at the station out of nowhere.

Astronaut Ricky Arnold wears a harness to train for zero gravity in space.


To be ready for all possibilities in space, astronauts go through a tough training program. NASA astronaut Ricky Arnold is preparing for a long mission on the ISS. He is set to leave in March 2018.

“We are training every day,” Arnold told TFK. “No days are alike.” Arnold is a former science teacher. He has been to space before. But his last mission lasted only 12 days. “We are going to be up there for six months,” he says. “Things can change rapidly. We need to be prepared.”

Arnold’s space training includes visits to Russia to learn about the Soyuz capsule.


A Unique Lab

The ISS is a giant flying space lab. It is operated by the United States, Russia, Japan, Europe, and Canada. It is the size of a football field. Astronauts from around the world live and work together. They spend much of their time doing experiments. They also observe Earth and make repairs to the station.

Mission training starts about two years before liftoff. It covers many subjects. These include astronomy, geology, aviation, and photography. “Astronauts also learn about the science experiments they will do in space,” says Tamara York. She is a training officer at NASA’s Johnson Space Center.

Arnold puts on a space suit with the help of a NASA trainer.


One tough task for astronauts on the ISS is going outside the station to do repairs. Astronauts prepare for spacewalks by diving in NASA’s Neutral Buoyancy Lab, in Houston. It is the world’s largest pool. The conditions there are close to those in space.

Safety First

Arnold’s training gets him ready to handle problems that might come up in space. Astronauts learn what to do if there is a fire on the station. They find out how to fix parts of the ISS. Arnold even trained at a hospital emergency room.

“If you need stitches, it’s going to be you or one of your buddies doing it for you,” he says.

Arnold looks at medical supplies. There are no doctors on the ISS.


Astronauts are weightless in space. They must relearn how to get dressed and go to the bathroom. They get tips from other astronauts. “On my first mission, a guy told me the best way to set up my sleeping bag,” Arnold says. “That was very helpful.”

Arnold says a safe mission always involves working well with a crew. “You are part of an international team. You work together to make something spectacular spectacular J.A. BRACCHI—GETTY IMAGES very impressive (adjective) The view of the ocean was spectacular. happen,” he says. “That sense of teamwork is the best part of the job.”

A New Class

These men and women are NASA’s newest astronauts.


It’s not easy to become a NASA astronaut. Earlier this year, 12 people were selected for NASA’s new astronaut class. The seven men and five women were chosen from a field of more than 18,000 applicants. Candidates need a degree in engineering, biological science, physical science, computer science, or math. They must also pass a comprehensive physical exam.

The new astronauts have already begun a two-year training program at NASA’s Johnson Space Center, in Houston, Texas. They will study spacecraft systems, aviation, spacewalking skills, and the Russian language.

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