Spacesuits are designed to protect the astronaut from the harsh conditions found in space. They are in fact enclosed environments in which the wearer can work in space in relative safety and comfort.
The spacesuit has to meet several requirements to protect the wearer in space. It must protect the wearer from the unfiltered heat of the sun which it does by a water cooling system consisting of small plastic tubes threaded through the inner suit. This inner suit also contains a drinking bag containing water and a waste collection bag to collect human excreta. Over this inner garment is fitted a pressure garment with flexible joints allowing the user to move around relatively freely. The suit must also be designed to stop harmful radiation and dust particles which could puncture the suit so the final two layers are made of tough abrasion resistant Teflon coated fabric. The helmet of the spacesuit is fitted with protective visors to protect against space dust and the harsh brightness of the sun.
On the astronaut's back is fitted the Primary Life Support System which contains enough water and oxygen to sustain living conditions for several hours away from the spacecraft. A back up pack is also fitted so that an extra thirty minutes of air and water is available should an emergency arise. Over the last few years a special backpack has been in use called the MMU (Manned Maneuvering Unit). This device allows the astronaut to move around freely up to one hundred metres from the spacecraft. Powered by nitrogen gas the wearer controls adjustable nozzles to move around in space without the need to be physically attached to the spacecraft by a safety line.
