NASA
EVA (spacewalk)
Working outside the spacecraft, in a suit that is itself a spacecraft.
An extravehicular activity is several hours of work in a pressurised suit with its own oxygen, cooling, power and radio. The hard part is not the vacuum but the pressure difference: a suit inflated to a workable pressure becomes stiff, so every hand movement fights the glove, and crews come back in with wrecked forearms. Before going out they spend hours breathing pure oxygen to purge nitrogen from the blood, for exactly the reason a diver ascends slowly. The station has now supported well over two hundred and fifty of them.
Where it has come up lately
NASA Space Station
NASA Space Station
ESA
NASA Space Station
NASA Space Station
Related terms
Life support (ECLSS)
The machinery that keeps the air breathable and the water drinkable, indefinitely.
What weightlessness does to people
Bone loss, fluid shift, weakened hearts and eyesight that does not always come back.
Docking and berthing
Two ways to attach a spacecraft to a station: it flies in, or it is caught and bolted on.
Expedition
The numbered crew rotation aboard the space station, roughly six months at a time.
Questions
What is EVA (spacewalk)?
Working outside the spacecraft, in a suit that is itself a spacecraft.
Why does it matter?
Before going out they spend hours breathing pure oxygen to purge nitrogen from the blood, for exactly the reason a diver ascends slowly. The station has now supported well over two hundred and fifty of them.