What training is required to become an astronaut?

Astronauts go through years of tough training before they can travel to space. They study science, engineering, and mathematics. Physical fitness is very important, so they train their bodies through swimming, running, and weight exercises. Astronauts also learn survival skills in case of emergency landings on Earth. They practice using space suits and working in mock versions of the International Space Station. They even learn to speak Russian because many missions involve working with Russian astronauts. Finally, they spend time in simulators that copy the feeling of space travel, so they know what to do during launch, in orbit, and when landing back on Earth.