Space travel to the moon, Mars, and beyond can expose astronauts to extreme conditions, causing potential health issues. To prepare for future long-duration missions, NASA studies how the effects of space—changes in gravity, radiation, and more—impact "model organisms," or other kinds of life that are biologically similar to humans. New findings from a study using fruit flies on the International Space Station suggest that space travel has an impact on the central nervous system, but that artificial gravity provides partial protection against those changes.

"Microgravity poses risks to the central nervous system, suggesting that countermeasures may be needed for long-duration space travel," said Dr. Janani Iyer, a Universities Space Research Association (USRA) project scientist at NASA's Ames Research Center in California's Silicon Valley and an author on the paper published today in Cell Reports.

Space is a hostile, extreme environment. It's only a matter of time before ordinary people are exposed to this environment, either by engaging in space tourism or by joining self-sustaining colonies far away from Earth.

To this end, there needs to be a much better understanding of how the environmental dangers of space will affect the biology of our cells, tissues, organs, and cognition. Crucially for future space colonies, we need to know whether we can easily reproduce in environments other than those found on Earth.

The effects of radiation on our cells, producing DNA damage, are well documented. What's less clear is how lower levels of gravity, what scientists call microgravity, will affect the mechanisms and rhythms taking place within our cells.

Scientists are only just beginning to investigate how activity in our cells might be affected by exposure to microgravity. Crucially, experiments on embryonic stem cells, and models of how embryos develop in their first few weeks in space, will help us determine whether it's possible for humans to produce offspring in the extraplanetary colonies of the future.