What time zone do they follow in the ISS?

Question: What time zone do they follow in the ISS?
- Keywords:
  ISS,
  time zone
Asked by AstridSmall to Simon, Julia, Delma, Andrew, Alex on 10 Dec 2015. This question was also asked by will.
- Simon Challis answered on 10 Dec 2015:
  
  Hi AstridSmall!
  
  ISS works on Greenwich Mean Time (GMT) which is not a bad time to pick considering there are 5 main control centres over the world in the US/Canada, Germany, Russia and Japan.
  
  And for us in Europe this is really great because it means that the crew day (normally the busiest part of the day) is almost the same as our day time.
  
  Imagine the control centre in Houston or Japan… these guys have to be super alert in the middle of their night time incase the crew has any questions/problems with their activities!
  
  Its also sometime inconvenient for the crew who want to talk to their family when they are not working but somehow GMT works for everyone and their are no plans to change it!

Question: What time zone do they follow in the ISS?