Space flight is getting serious: Amid a constant barrage of news headlines replete with the promises of the rapidly growing commercial space travel industry, some inquiring minds are taking a step back to consider whether our bodies can actually stand up to long periods spent in the far reaches of our solar system, The New Yorker writes.

Space travel has long been understood to have significant impacts on astronauts’ bodies, with scientists noting how prolonged time in low-gravity settings lengthens astronauts’ spines and leads to muscle wasting and lower bone density, leaving astronauts chained to their workout gear in order to maintain a healthy physique. Still, the increasing number of space travellers as the commercial space race heats up is now offering scientists and observers a scientifically meaningful sample size with which to assess the possible impacts of space travel.

Enter the NASA twins study: On 2 March 2016, US astronaut Scott Kelly returned to Earth after nearly a year in space — marking the longest-ever spaceflight by any American. After landing he experienced severe physical effects, including nausea, dizziness, joint pain, swelling, and a rash. While these symptoms were not in and of themselves exceptional, one key feature of Kelly offered NASA scientists a unique opportunity to assess the effects of space travel on his body — the fact that he was a twin. The NASA twins study, as it came to be known, compared Scott Kelly’s body with that of his brother, former astronaut Mark Kelly, with the research ultimately published in the peer-reviewed journal Science.

The results showed that extended space travel had seriously impacted Scott Kelly’s body and brain. Researchers found signs of cognitive decline, extreme inflammation, and potential long-term brain changes, with some tests showing markers of inflammation in Kelly’s blood had risen to levels difficult to measure with conventional lab equipment.

The question boils down to whether or not the effects of space travel are reversible — and whether or not it’s ethical to figure that out. For space travel boosters, there’s no alternative. “At some point, we’re going to have thousands of people living or working in space,” Christopher Mason, a principal investigator on the study, said. “We need to understand how to do that safely.” Others are not so sure. Mathias Basner, a University of Pennsylvania professor and member of the twins study, told the outlet that early indications suggest that space travel could cause profound structural changes in the brain — some of which may be reversible, some of which may not.

It’s going to take time — and a lot more data — before we have clear answers, but growing interest in space travel should fuel more research in the area. According to Mason, “we’re starting to see a biological signature of space. Soon, we’ll be able to say, This is what will happen to you if you get a three-day dose of space. That is what will happen with a three-month dose.”

Tags: