A manned mission to Mars would mark the single-greatest accomplishment in NASA’s history, but the journey doesn’t begin in a rocket – instead, it begins in a dome located in a very Mars-esque part of Hawaii. The mission, dubbed the Hawaii Space Exploration Analog and Simulation (HI-SEAS) sent six would-be Martian inhabitants into an isolated domed environment on October 15. The mission is planned to last eight months. It will be the longest space travel simulation ever conducted on U.S. soil.

“I think it’s important to advance science and technology and to continue exploring, and to one day not have to rely not only on Earth and to have more places for humans to live and thrive and keep continuing,” said HI-SEAS crew member Jocelyn Dunn minutes before entering the habitat.

If the length of the mission seems excessive, consider that the journey to Mars and back could take as long as three years with current technology.

The dome, which measures 1,500 square feet, isn’t meant to simulate actual Martian conditions. The “astronauts” will live in work in normal clothes and atmospheric conditions, save for a simulation space suit they’ll have to wear if they want to step outside for any reason. Instead, the HI-SEAS experiment is all about determining whether or not these six people can successfully cohabitate in such cramped quarters.

“The purpose of this mission, as well as the one before it and the one after it, is to look at crew cohesion, and see how that predicts performance,” explained principle investigator Kim Binsted, a UH Mānoa associate professor of information and computer sciences. “So we are going to look really closely at the crew’s psychology, over these eight months.”

Even though the participants won’t have to deal with harsh Martian conditions, the experiment won’t be without its sacrifices. Over a “last meal” at a popular local eatery, the crew members reminisced about what they’d miss most.

“I guess my biggest fear is losing contact with family and my niece,” said Dunn. “She is only two and a half and I don’t want her to forget me.”