Recycled Oxygen in Space

04 February 2008
Presented by Diana O'Carroll


This week, we find out how they manufacture oxygen on the International Space Station - a technique that astronauts must be 'over the moon' about! Plus, we ask how electric eels avoid self-shocking, and what gives a well loved old book that distinctive smell?

In this episode

Picture taken by STS-121 crew after departure from the ISS on July 15, 2006.

00:00 - Recycling Oxygen?

How is oxygen made and recycled on the International Space Station?

Recycling Oxygen?

We put this question to Mark Hempsell, Senior Lecturer, University of Bristol... 

The oxygen isn't strictly recycled.

The carbon dioxide that the humans breathe out is filtered out of the air with a molecular sieve and then simply dumped overboard.

The oxygen is created from the water that comes from the air and from the washbasins and from the loos.

After that water is cleaned up it is electrolysed. An electric current is passed through it and it is separated into hydrogen and oxygen.

The hydrogen is dumped overboard; the oxygen is fed into the cabin for the crew to breathe.


Add a comment