Send an all-woman crew to Mars…its cheaper

This article from Slate on the discovery (whisper it) that women generally have a lower weight and a lower metabolic rate than most men, therefore the first manned mission to Mars should be predominantly or all female because it would be cheaper to launch women and keep them fed on Mars.

Last year I [author Kate Greene] took part in a NASA-funded research project called HI-SEAS (Hawaii Space Exploration Analog and Simulation). It required that I and five other crewmembers live as astronauts on the surface of Mars. We didn’t leave Earth, obviously, but for four months we were cooped up in a geodesic dome on the side of the very red, very rocky, very Mars-like Mauna Loa volcano in Hawaii. Our food, water, power, and communications were limited, and we were only allowed to exit the habitat if we wore mock spacesuits. So many Martian hassles, so little glory.

Author Kate Greene during a mock Mars mission.

Author Kate Greene during a mock Mars mission.

Courtesy of Sian Proctor

This was the first HI-SEAS mission—a third starts this month—and it was designed mainly to study the types of food Mars explorers might eat. I was the crew writer, blogging for Discover and the Economist, and since I had the scientific background and interest, I conducted a sleep study, too.

I collected and managed the crew’s sleep data over the course of the experiment. One device we used to track sleep was the sensor armband from BodyMedia, which also provides estimates of daily and weekly caloric expenditure. While I didn’t know which data belonged to which subject due to anonymity requirements, I could see each subject’s sex. Over time I noticed a trend.

Week in and week out, the three female crew members expended less than half the calories of the three male crew members. Less than half! We were all exercising roughly the same amount—at least 45 minutes a day for five consecutive days a week—but our metabolic furnaces were calibrated in radically different ways.

During one week, the most metabolically active male burned an average of 3,450 calories per day, while the least metabolically active female expended 1,475 calories per day. It was rare for a woman on crew to burn 2,000 calories in a day and common for male crew members to exceed 3,000.

We were only allowed to exit the habitat if we wore mock spacesuits. So many Martian hassles, so little glory.

The data certainly fit with my other observations. At mealtime, the women took smaller portions than the men, who often went back for seconds. One crew member complained how hard it was to maintain his weight, despite all the calories he was taking in.

The calorie requirements of an astronaut matter significantly when planning a mission. The more food a person needs to maintain her weight on a long space journey, the more food should launch with her. The more food launched, the heavier the payload. The heavier the payload, the more fuel required to blast it into orbit and beyond. The more fuel required, the heavier the rocket becomes, which it in turn requires more fuel to launch.

Wait, according to feminist theory, the physiological differences between the sexes are socially conditioned. That’s why men have much greater upper body strength.

But I digress…

The cost of a Mars mission has gone down since 1989, apparently

According to Robert Zubrin, aerospace engineer, author, and president of the Mars Society, a round-trip mission to Mars could cost as little as $30 billion. While this is a low-ball estimate that ignores many of the details, it suggests that a manned Mars mission might not cost $450 billion, an amount proposed by NASA in 1989 that many believe is close to the upper limit for such a mission. Many of today’s estimates tend to be around $100 billion.

Its not just that I’m a pragmatist (or pessimist) but you’ll never, ever get the US Government to spend as low as $30 billion anywhere. Just look at the budget for the War on Terror or the War on Drugs.

Which gets me back to my previous comment, that if mankind really, seriously want to go to Mars, then more than one country needs to be involved.

Harry Jones, of NASA Ames Research Center, says that he too noticed the average female and male calorie requirement differed significantly and published on the topic in the early 2000s. “For a Mars mission, life support will be a major cost,” he says. “It is expected that oxygen and water can be recycled, but not food. Reducing the crew’s calorie requirement would cut cost.”

But is it a significant cost relative to the cost of lifting everything else?

Besides which

As reasonable as an all-female Mars mission is from an economic perspective, some might find the idea offensive. After all, it’d be an expedition that fails to represent half the world’s population; an all-female Mars crew would strike many as exceptionally biased.

Then again, space-mission design has always been biased in one way or another. Exploration in general is nothing if not political, dictated by the people with the money and power to choose the face of the expedition. Right now, it’s unlikely that those with the power to do so would agree to fund a crew of small female astronauts even to save money.

Again I think its more likely that the crew will probably be 2 male and 2 female, or 3 male and 3 female.

If it ever happens at all.