Women (probably) make for better astronauts. So should the first crew to Mars be all-female?

“That’s one small step for man… one giant leap for mankind”. Neil Armstrong’s famous declaration tellingly illustrates that the first generation of Moon landings was a male-dominated affair. Perceptions back then were that women simply did not have ‘the right stuff’ to make it in space. This was, of course, nonsense.

These days progress has been made and now the astronaut corps found around the world are much more balanced in terms of gender.

But could it be that females have the edge when it comes to putting humans back on the Moon, or travelling to Mars and beyond?

A recent study by European Space Agency’s (ESA) medical team, concluded that “there may be a number of operational advantages to all-female crews [for future long-duration missions]”.

The work considered a theoretical group of astronauts and made estimations of the life support requirements and consumables that such a crew would require.

They concluded, not surprisingly, that because females are, on average, smaller and lighter than males, they need less food and oxygen over the course of a mission.

This is key, as getting ‘stuff’ – spacecraft, robots, humans, and everything needed to sustain them – into space takes large amounts of energy.

The laws of physics demand that to orbit a planet, or to escape its gravity and fly to another, the ‘stuff’ needs to accelerate to very high speeds. The more ‘stuff’, or mass, you want to get into Earth orbit, or to the Moon or Mars, the larger rocket you need.

So, if women are lighter, and eat less, should the first crew to fly to Mars be all-female?

The ESA study was a follow-up to an earlier paper by the same researchers that considered a theoretical all-male crew. Sex disaggregation in research is a good thing, as there are biological differences between sexes, and understanding these differences results in better-informed decisions.

But as Angela Saini, a journalist and author who has researched the impacts of sex-based research says: “There is actually no real-life 'default' male – every man is different from the next, just like every woman is.

"While it's great that women have been studied, the more important takeaway is that individual astronauts should obviously be considered.”

Getting humans to Mars and back safely is a monumental challenge. A round trip would take around two years, with the crew having to endure a harsh environment, bombarded by solar wind.

Also, as they ventured further away from Earth, communication delays would increase, with messages taking many minutes just to travel one way, rendering normal conversations with anyone back here on Earth impossible.

Once on the Red Planet, after nine months in transit and living in a weightless environment, the crew would have to be physically and mentally capable of living on the surface of Mars before taking the return trip home. Solving the challenges of keeping astronauts safe and well will require a staggering number of considerations.

The ESA study showed that, just as on Earth, the resources needed to sustain crew when they exercise are higher than at rest, but exercise is vital to ensure that astronauts’ bones and muscles are strong enough for them to function when they land.

HIFIm, a revolutionary new exercise device invented by John Kennett, Director of Physical Mind London, might hold the answer.

Smaller and lighter than current exercise equipment, the workouts are carried out on a bench-like device and are based around jumping movements, rather than running or cycling, and could revolutionise in-space exercise programmes.

Kennett says: “The ESA has proven jumping just four to six minutes a day mitigates the effects of being in microgravity. This means that HIFIm could reduce the time astronauts need to exercise by over 80 per cent”.

So using the new device could also reduce the resources the astronauts need and lessen the payload any rocket would have to carry.

As well as staying fit and healthy individually, any crew must also function well collectively. Whilst humans haven’t yet travelled to Mars, research has been carried out into how people function in confined, isolated environments for long periods of time, and this shows that a diverse crew is key to success.

Susan Charlesworth, Director of Oxford Human Performance, and a specialist in human factors for planning space missions, says: “Men and women often have different, complementary leadership and conflict management styles which temper one another, leading to better cohesion over extended periods. A crew that is diverse in many characteristics maximises their likelihood of successful team working.”

Overcoming these extreme environments and challenges is also part of why human spaceflight can be inspirational to so many people, and the first mission to Mars will surely captivate the imagination. However, to reach the widest possible audience inclusivity is vital.

Saini says: “One of the mistakes of earlier eras was to assume that all women were incapable of going into space. It would be just as damaging to assume that all men were unsuitable.

"I would hate for young boys to feel they couldn't dream of being astronauts, just as I hate that young girls were ever made to feel that way.”

Space agencies spend a lot of time and effort selecting their astronauts, finding people with the right mix of skill and personality that is needed to thrive in space. These astronauts are then carefully combined into crews, taking account of the specific demands of any given mission.

The first journey to Mars will be risky, arduous, and daunting. The crew that takes that step will be painstakingly chosen, and will most certainly have the right stuff to undertake what will be a monumental leap for humankind, whatever their gender.