Being in space probably won't hurt you, new study shows

What happens to your body when you live in space? That's the question that NASA set out to answer — with twins.

In 2015, astronaut Scott Kelly spent a year aboard the International Space Station, while his identical twin brother Mark did not. After Scott returned, scientists conducted a "meticulous" investigation of both twins, analyzing the changes that occurred in their bodies to understand the effects of long periods spent away from our planet. Four years later, the results of NASA's study are ready to be shared.

Published in the journal Science on Thursday, the findings might seem a little underwhelming at first glance. While Scott Kelly underwent some physical changes during his time in space, "the vast majority" of those changes went back to normal within six months. Furthermore, Scott was about as healthy as his brother during his time at the International Space Station in terms of physical, mental, and genetic health.

But while nothing so radical as a DNA transformation or a new mutation occurred, this data still provides NASA with valuable information about the changes an astronaut's body can go through in space — and we can use that information to better protect our astronauts who venture out into orbit, to the moon, to Mars, and eventually, beyond.

NASA is taking these results as a good sign: In a statement released on Thursday about the study, the agency concluded "human health can be mostly sustained" over the course of a year in space. And one of the study's investigators, Michael Snyder, said "it's reassuring to know that when you come back things will largely be back to the same."

NASA plans to conduct further studies on the effects of living in space on the human body with more missions of varying lengths. Read more about the results we have so far at Gizmodo.