In outer space there is no air to breathe and the temperature can quickly change from being very hot to very cold. To survive astronauts must wear spacesuits. They are like an astronaut’s personal spacecraft, allowing them to do important jobs – such as repairing the space station.

Lots of layers

Spacesuits have 14 layers of material to help keep astronauts safe. The liquid cooling and ventilation garment makes up the first three layers. On top of this garment is the bladder layer. It creates the proper pressure for the body. It also holds in the oxygen for breathing. The next layer holds the bladder layer to the correct shape around the astronaut’s body and is made of the same material as camping tents. The rip stop liner is the tear-resistant layer. The next seven layers are Mylar insulation and make the suit act like a thermos. The layers keep the temperature from changing inside. They also protect the spacewalker from being harmed by small, high-speed objects flying through space. The outer layer is made of a blend of three fabrics. One fabric is waterproof. Another is the material used to make bullet-proof vests. The third fabric is fire-resistant.

Life support system

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.

The PLSS also holds water-cooling equipment, a fan to circulate oxygen and a two-way radio. A caution and warning system in this backpack lets spacewalkers know if something is wrong with the suit. The unit is covered with protective cloth layers. 

Spacesuit gloves have heaters in the fingertips to stop an astronaut’s fingers from getting cold! EVA gloves are made to protect astronauts from the space environment. They are also made so spacewalkers can move their fingers as easily as possible. The fingers are the part of the body that gets coldest in space. These gloves have heaters in the fingertips. A piece called a bearing connects the glove to the sleeve. The bearing allows the wrist to turn.

Astronauts see out of a clear plastic bubble, and also have a visor to protect them from the Sun’s harmful rays. The helmet keeps the oxygen at the right pressure around the head. The main part of the helmet is the clear plastic bubble.

The bubble is covered by the Extravehicular Visor Assembly. The visor is coated with a thin layer of gold that filters out the sun’s harmful rays. The visor also protects the spacewalker from extreme temperatures and small objects that may hit the spacewalker.

A TV camera and lights can be attached to the helmet.

Display unit

This module is the control panel for the mini-spacecraft. Switches, controls, gauges and an electronic display are on the module. The astronaut can operate the Primary Life Support Subsystem from this module.

Astronauts can attach their boots to special foot restraints on the space station to make working in space easier.

Flying free

This space jetpack is called a “Manned Maneuvering Unit”. It was used by astronauts in the 1980s to travel in space without being tied to their spacecraft. Today, astronauts have smaller versions in case of emergencies. The MMU is a self-contained astronaut backpack propulsion device that allows astronauts to venture untethered from an orbiting spacecraft.  The unit is powered by 24 nitrogen gas thrusters, and its main structure is aluminum.  Other elements include two 16.8-volt silver zinc batteries, a control electronics assembly, and two hand controllers.

To use the MMU, an astronaut exits the Space Shuttle crew compartment through an airlock into the cargo bay.  There the astronaut dons the MMU and releases himself from the flight support station.  To maneuver in space, the astronaut uses the hand controllers.  The control electronics assembly translates the hand controller movements and fires the thrusters.  The astronaut can activate an auto-pilot system which will hold his attitude.

When not in use, the MMU is stowed and recharged in the flight support stations located in the forward end of the orbiter’s payload bay.

 

Picture Credit : Google