A little over one year ago, six fake astronauts returned to the real world after spending 520 days in isolation. They were part of the Mars500 experiment, created to simulate a manned mission to the planet Mars. During their stay in the simulated spaceship near Moscow, the volunteers lived in cramped spaces without fresh food sunlight, or air.

Today, the European Space Agency (ESA) revealed that Mars 500 revealed that astronauts on such a long mission will need their schedules and diet to be rigidly maintained. The fake astronauts, living without sunlight, began letting their sleep patterns slip.

“Although there was an issue with sleeping patterns getting out of phase, it is amazing that the human body can adapt to a total lack of Sun,” said Diego Urbina, one of the six “marsonauts” in the Mars500 experiment.

The ESA is currently looking into ways to help curb sleep troubles for future astronauts. An ESA astronaut will be measuring hormones linked to sleep during a six-month tour of the International Space Station (ISS) this year, and the crew at the Concordia Antarctic base will have its sleep patterns monitored during the polar winter. The research, stated the ESA, could also help those on Earth who keep odd schedules or those who have issues with sleep.

Another finding of the Mars500 research was that humans do not absorb salt constantly. Instead, the fake astronauts’ kidneys were found to process salt on a weekly cycle.

“These results are showing why we participated in the Mars500 study.” said Jennifer Ngo-Anh, the ESA’s study manager. “We expect even more interesting results now that researchers have had a year to analyse data from this unique long study.”

(Image courtesy ESA/IBMP)