An astronaut walking in space must wear clothing that protects him from the sun rays why?

NASA's Extravehicular Mobility Unit, or EMU, is like a personal mini-spacecraft. Learn more about why astronauts wear spacesuits. The spacesuit used on space shuttle and International Space Station missions is like a personal spacecraft.

The spacesuit provides protection and a means for survival for the astronaut. Like a small spacecraft, the spacesuit allows astronauts to work outside of their space vehicles. Working outside of a spacecraft while in space is called an extravehicular activity, an EVA or a spacewalk.

The white spacesuit an astronaut wears during a spacewalk is called the extravehicular mobility unit, or EMU. Extravehicular means outside of the vehicle or spacecraft. Mobility means that the astronaut can move while wearing the suit.

Astronauts sometimes go on spacewalks to help build the space station. Sometimes the purpose of a spacewalk is to fix something that is broken. Spacewalks have been used to assist in capturing satellites in space.

When the Hubble Space Telescope needs repairs, spacewalkers are needed to do the job. Some spacewalks may last as long as eight hours. Like a spacecraft, a spacesuit protects an astronaut from the dangers of space.

The spacesuit completely covers a spacewalker's body. The pieces of the suit interlock so that none of the spacewalker's skin is exposed to space. Without spacewalks, much of the work that needs to be done in space would not be accomplished.

And a spacewalk would be impossible without the protection of a spacesuit. NASA spacesuits have many pieces and parts. Learn about the parts and why each piece is important.

The PLSS is worn like a backpack. It provides astronauts many of the things they need to survive on a spacewalk. Its tanks supply oxygen for the astronauts to breathe.

It removes exhaled carbon dioxide. It contains a battery for electrical power.