Astronauts: Do You Have What It Takes? - Season 1 Episode 4 -

In week four the candidates leave the German Space Agency behind and head to a secret location in Sweden to face astronaut Chris Hadfield's toughest tests so far. Here, in a military installation, the panel will discover who can cope with a crisis in space. The candidates will be put through a potentially life threatening test of hypoxia – a deadly condition in which the body is deprived of oxygen.