NASA has sent more than 50 women into space over the past 50 years, compared to hundreds of men. As the agency begins plans for visiting and colonizing Mars, the difference has become important. NASA doctors lack statistical data that would help them understand the effects of long-term exposure to space on women’s bodies.
The issue came to the fore at NASA’s Human to Mars conference, held last week at George Washington University in Washington, DC. Women at the conference said it is critical to recruit more female astronauts and to send more of them on longer missions. It is critical, they said, to understand how women respond physically and mentally to the challenges of zero-gravity environments.
“We don’t have as big of a database of women [astronauts], so it’s always a little harder to get statistical data – but we do see differences,” said Ellen Stofan, NASA’s former chief scientist.
Doctors and physiologists are just beginning to understand the effects of long space missions can affect the human body. For example, it is known that astronauts lose bone and muscle mass in space – that’s why their schedules include two hours of daily exercise. University of Michigan researchers have recently found that astronauts’ brains change shape in space. No one knows why.
Extended space missions will expose travelers and crew to more radiation. Women are sensitive to radiation-induced cancers in the lungs, thyroid, breasts, and ovaries. But those aren’t the only differences.
For example, women seem to be less vulnerable to an eye condition called visual impairment intracranial pressure syndrome, which affects some male astronauts. Women may be more vulnerable to urinary tract infections.
These differences may not be important on short flights that stay close to earth. (And for the record, NASA has never sent a woman further into space than low Earth orbit.) But they are likely to blossom into full importance on a Mars mission.
The American space program currently has 44 active astronauts. Just 14 are women. There are five astronauts at the International Space Station right now. Only one is a woman.
NASA is recruiting more women into its corps of astronauts. Women’s health issues will require much more study as the agency plans long trips to visit and colonize Mars.