Thanks @suesa, nice story to return to after my holidays! I was thinking how a bioengineered solution used in deep sea might be adapted for use in space, since research points out to anaerobic organisms that survive in deep sea trenches and hydrothermal vents and which are suspected to exist in places like Jupiter's Europa... Maybe another parallel story with Michelle, where she is asked to come up with a way of humans living in another planet/satellite? Thanks again, really entertaining.