(Photo: Carmel Johnston)

This day last year six scientists entered a dome on a mountain in Hawaii and lived as you might on Mars. They slept in tight quarters and only entered the outside world in spacesuits, while also trying to deal with the psychological pressures of seeing only the same five other people each day, every day, for 365 days. 

That, in fact, was the main focus of the experiment: Could anyone live peacefully, long-term with five other people in a dome the size of a small house? 

It turns out, they mostly can, though not without a few difficulties.

The scientists emerged from the dome Sunday, back into the real world, but not before facing the press. 

“It is kind of like having roommates that just are always there and you can never escape them,” the mission’s commander, Carmel Johnston, said, according to the BBC. “I’m sure some people can imagine what that is like, and if you can’t, then just imagine never being able to get away from anybody.”

The mission was funded by NASA, and, more than the psychological study, was also an opportunity to conduct research, while the scientists—four Americans, a German physicist and a French astrobiologist—subsided in almost total isolation on a mountain in Mauna Loa, though they were still able to write blog posts.

“Given what it takes to keep people alive in the void—to keep them healthy on Mars for just a year—I can basically promise that by going to space we’ll learn what it takes to keep people healthy in places with heat, light, and gravity,” one crew member, Sheyna Gifford, wrote in a post. “We’ve already started.”

NASA’s experiment was 365 days long, though it fell short of the record, held by Russia, which previously stowed away a crew of six for 520 days. That group emerged, mostly fine, in November 2011.