Research on generating oxygen from water found on other planets could help support future missions to Mars and the Moon.

Researchers from the University of Glasgow took a series of gruelling flights into microgravity to study how the different gravitational pull of other planets could affect the process of electrolysis.

Electrolysis uses electric current to split water into its constituent gases – hydrogen and oxygen. Oxygen is vital to space missions as it allows astronauts to breathe and refuel their rockets but currently, space missions carry the oxygen they need with them in bulky tanks.

While the process of electrolysis on Earth is well-understood, much less is known about how it might function in the lower-gravity environments of Mars, where the pull of gravity is one-third that of Earth, and the Moon, where it is just one-sixth.

So as plans to establish permanent bases on the Moon and Mars gather pace, space scientists want to find sources of oxygen in the ice found on planetary surfaces - as electrolysing the melted space ice could free missions from the need to carry all of their own oxygen. This would help proposed long-term habitations like NASA’s lunar station become self-sustaining.

In a new paper published in Nature Communications, the research team, led by Dr Bethany Lomax, describe how they designed and built an experiment to take into the microgravity environments created during 'parabolic' flights. In those flights, aircraft create brief periods of weightlessness by flying in alternating upward and downward arcs.

Aboard an Air Zero G Airbus A310 flown from an airport in Germany by the European Space Agency and Novespace, the researchers deployed four electrolysis cells built into a small centrifuge.

As the plane arced through microgravity, they were able to recreate the lower gravitational conditions of the Moon by spinning the centrifuge at different speeds. While doing so they measured the bubbles of oxygen produced.

Dr Lomax, who took part in the flights and is now a research fellow at the European Space Agency, said, “The process of taking the flights to get those results was challenging, not just the nausea of the constant climbs and drops during the parabolas but also in arranging to travel from the UK to Germany during the pandemic. The whole team worked really hard to get the experiment ready in time for flight.

“However, it was worth for it the observations we were able to make, which we hope will be of real use to future space mission planners.”

Dr Mark Symes, of the University of Glasgow’s School of Chemistry, a co-author of the paper added: “The experiment that Dr Lomax designed was ambitious and required a lot of effort to, literally and metaphorically, get off the ground. However, the results are a valuable contribution to the growing body of science that will underpin long-term human habitation of other planets. I’m looking forward to seeing how future work can build on these findings.”

The research was supported by funding from the European Space Agency’s Networking/Partnership Initiative, the UK Space Agency, the Engineering and Physical Sciences Research Council (EPSRC), the Institution of Mechanical Engineers, and the Royal Society.

Researchers from the Universities of Glasgow and Manchester, the European Space Research and Technology Centre in the Netherlands and the Johns Hopkins University Applied Physics Laboratory in the United States contributed to the paper, titled ‘Predicting the efficiency of oxygen-evolving electrolysis on the Moon and Mars.