The physical toll of nine months on the ISS

Swollen faces, struggling to walk and a loss of vision are just some of the effects of a prolonged trip to space, but scientists say the health of astronauts can help people back on Earth.

Astronauts Butch Wilmore and Suni Williams have captured the world's attention for their drawn out drama on the International Space Station.

Back on earth after nine months, their bodies and minds will continue to be under scrutiny by scientists including New Zealand space medicine researchers looking for ways to fight cancer and treat degenerative diseases.

"We can use the data learnt from space to apply it back to the health of people on earth, [it's] what we call translational medicine," says Dr Lisa Brown, surgeon and space medicine researcher at Auckland University.

Brown is involved in research on radiation and carcinogenesis - the development of cancer - that looks at the dangers of increased radiation exposure, such as what would happen if travelling to Mars.

One project is studying the effects of radiation on the skin and astronauts' experiences of melanoma, a deadly skin cancer that afflicts New Zealanders and Australians at record levels.

"We know that astronauts have quite a high rate of melanoma, or non-melanoma such as squamous cell carcinoma," Brown says.

"We're looking at the similarities between space travel and ionising radiation and also how we could use knowledge gained from that in terms of helping people back on earth."

It is widely known that astronauts suffer from dizziness, difficulty walking and puffy faces in the early days after returning to Earth, and more serious, long term health problems.

But as older astronauts, Wilmore, 61, and Williams, 59, will be giving researchers new information, says Brad Tucker, astrophysicist and cosmologist at Canberra's Australian National University.

"There will be daily monitoring for their own health improvements and all the issues that arise from long-duration space flights but at the same time there is all the interest from the research side that people will want.

"Most of the data on human space flight comes from 20 to 40-year-old Russian and American airforce and navy pilots, it's a very small group that most of the data comes from. The fact that they are older and they were in there for nine months, that will be interesting."

Tucker says Williams and Wilmore are the most famous astronauts in decades after their eight-day trip to the space station stretched to nine months, and not because of the technical hitches.

"This is a human story," he says.

How they handled isolation and each other's company, the daily stresses and rigid routines intrigue people, he says. Add to that the fact that Williams and Wilmore were test pilots on a mission that did not go to plan.

"They were cool customers," Tucker says. "They were selected for a reason."

"When things go wrong in space they usually never go a little wrong. There is no such thing as minor problems in space, it always requires a lot of work to fix even if it's not catastrophic.

"To have that ability to just be able to go with it and adapt to it knowing that decisions that you're making are at the risk of potential life or vast equipment but yet keep a smile on your face ... that takes a special person."

Brown, the first New Zealander to study space medicine at the University of Texas with NASA, says New Zealand has a significant role in the space industry, both with rockets and health.

"With the rocket launches [by RocketLab] I think we've proven to the international community that New Zealand is really a big player in space."

In a similar way, the University of Auckland's space health network pulls together the expertise of different researchers with a focus on translational medicine.

"New Zealand has a lot to offer and I think that's quite exciting for growth of the sector."

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