Who makes space suits

When the first astronauts move into the International Space Station (ISS) this month, they will often be wearing what is arguably the most expensive clothing on our planet. A spacesuit for outdoor work costs twelve million dollars because it simulates a piece of "earth" at an altitude of almost 500 kilometers. The suit protects its wearer from extreme temperatures, micrometeorites, cosmic and ultraviolet radiation, supplies vital oxygen and provides means of communication and transportation.

The "primary life support system" is carried on the back like a backpack. It regenerates the exhaled air: carbon dioxide is removed, oxygen is added. The pressure in the suit is only 0.29 bar pure oxygen. There are two reasons. The lower air pressure makes it easier to move in the near-vacuum of space and the suit itself does not have to be so robust. However, before getting dressed, the astronauts have to breathe in pure oxygen in order to reduce the concentration of nitrogen dissolved in the tissue. Otherwise, switching to the low pressure conditions in the suit could trigger a kind of diving illness.

An 80-milliliter drinking bag in the "upper torso" enables drinking while working in space; a kind of diaper for adults with a capacity of 900 milliliters absorbs the urine in the "lower" torso.

The suits of the American space agency Nasa, officially called "extravehicular mobility units", are manufactured under the supervision of the general contractor Hamilton Sundstran with the participation of 52 other companies. The European Space Agency Esa is developing its own outboard suits for the ISS together with Russian cooperation partners, in particular the Swesdo company.

The editorial team would like to thank the German "Raumfahrt Service International" for its support.

Did you know, that …

... the specified maximum duration of a space walk is seven hours, but generously designed limit values ​​allow even longer excursions? The longest outboard stay for American astronauts was completed by Pierre Thuot, Rick Hieb and Tom Akers, who on May 13, 1992 spent a total of 8 hours and 29 minutes in space while working on the communications satellite Intelsat.

... before the first planned space walk on the fifth flight of the space shuttle in 1982, the blower in the life support system of a space suit failed and the excursion was therefore canceled? It was the first and so far only major problem with a spacesuit in space.

... the astronauts of the international space station (ISS) will have a so-called safer that can bring them back to the vehicle in an emergency? During construction, the space shuttle will dock with the space station, so it can hardly undertake rapid rescue flights. The Safer (Simplified Aid for Extravehicular Activity Rescue), successfully tested in 1994, uses nitrogen pressure cartridges as a drive and is attached to the bottom of the life support system. It is controlled by a handheld control device.

... shuttle orbiters only carry three complete outboard suits, but have up to seven crew members? For emergencies, however, there are escape pods made of the same material as the space suits with their own oxygen supply, which can be retrieved by a shuttle.

From: Spectrum of Science 11/2000, page 120
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This article is included in Spectrum of Science 11/2000