Asked by: Gemma King, Plymouth
In 1967, a fire killed three American astronauts during a launch rehearsal of the first Apollo mission. The resulting inquiry led to extra testing of materials used throughout the space programme – and this included sniff-testing.
Non-toxic materials can still give off odours that make astronauts feel queasy, especially in the cramped confines of a space vehicle. That in turn can undermine the performance of the astronaut, putting the entire mission at risk.
NASA’s current ‘chief sniffer’ is George Aldrich. Sometimes known as ‘Nostrildamus’, he is tasked with smelling all objects that will be within the habitable areas of the International Space Station.
Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun facts.