See how NASA simulates year on Mars...on Earth's largest volcano

Ten months ago, six people volunteered to go off the grid in Hawaii for one year in the name of science. They've been living together, isolated from the world, in a two-story dome on Mauna Loa, the world's largest volcano. 

Powered by solar panels, their home and lab is a simulation of what the first human explorers of Mars might set up on the Red Planet, possibly in the next couple of decades. The dome is 36 feet in diameter, with a volume of 13,570 cubic feet that allow for two floors. The kitchen, dining area, bathroom, lab, exercise area, and common spaces are on a 993-square-foot ground floor. The crew bedrooms make up 424-square-feet of the top floor; and a 160-square-foot workshop, converted from a steel shipping container, is attached to the outside of the dome.

The tight quarters reflect the living conditions of future Mars explorers, who will have to spend several years together, including at least six months of travel both to and from Mars. The good news for them, so far, is that of the three men and three women scientists living in the Hawaiian dome since August 28, none has had to go home for psychological reasons yet.

"If things are going to go wrong, they're going to go wrong by the eight month point," Kim Binsted, a University of Hawaii professor who leads the experiment, called HI-SEAS (Hawai'i Space Exploration Analog and Simulation), told The Christian Science Monitor at the eight-month point in May.

"Though we don't know that for sure," she cautions.

The goal of this fourth and longest of the HI-SEAS missions, which are funded by NASA, is to learn how group dynamics play out under stressful conditions, such as the ones that explorers will one day encounter on Mars. This fourth planet from the sun is an inhospitable desert, with an average temperature of -81 degrees Fahrenheit, massive dust storms, and harsh radiation from the sun that can't be deflected by the planet's weak magnetic field, nor absorbed by its flimsy atmosphere.

Physically, exploring Mars will be a challenge. Psychologically, too. Astronauts venturing into deep space together for the first time could grapple with feelings of isolation, depression, and personality conflicts. This is why choosing a resilient crew will be key, says Dr. Binsted.

"Every crew is going to have its conflict, but I don't think it's possible to select a crew that over these long durations never has any conflict," she told the Monitor. "That's one of the morals of the story that we’re going to come away with," she says.

Though conditions on the active Mauna Loa, which rises nearly 14,000 feet over the Big Island, are not nearly as extreme as they are on Mars, the volcano is rugged and remote. Its surface is bare of plants or animals, and it's covered in volcanic basalt rock, as is Mars. Three other crews have already lived on the volcano in previous Mars simulations, two of them lasting for four months and the other for eight. Despite roommate quarrels, no one has abandoned the dome, says Binsted, except for one person who left for medical reasons.

Members of the current crew, some of whom are aspiring astronauts, spend their days much like the astronauts on Mars will: working on science experiments, preparing meals while the sun shines and powers the oven, and exercising to counter the effects of (pretend) minimal gravity. To relax during their free time, team members soak up sun on the "beach," an activity made possible by a heat lamp and a virtual reality headset. On weekends, they dance salsa.

To talk to the ground-control crew, or their friends and family, the Hawaiian astronauts have to endure at least a 20-minute delay in communications, as they would on far-away Mars. At the closest point possible given the orbits of the two planets, Earth and Mars are nearly 34 million miles apart.

Though HI-SEAS crew members do get outside on geological excursions, they have to leave the dome through an airlock to simulate depressurization, and with spacesuits on. A "ground crew" of 40 volunteers from around the world helps them with logistics.

Given that there isn't real-time communication, one of the ways researchers keep track of crew dynamics is by monitoring the distance between crew members and the volume of their voices through badges that everyone must wear.

"If two people never go near each other, maybe they're avoiding each other," says Binsted. A spike in the voice volume between two crew members could indicate they're fighting. 

But it appears that the HI-SEAS group is gelling, at least according to one team member.

"I think we've done remarkably well, compared to a lot of research I did for my Master's about what can happen in environments like this," crew architect Tristan Bassingthwaighte, a doctor of architecture candidate at University of Hawaii at Mānoa told the Monitor in a recorded video interview in March. "We don't have nearly as many of the reclusive tendencies that I thought would happen."

The final results of crew dynamics on this one-year psychological study will be published in about a year, says Binsted. Meanwhile, the next two HI-SEAS experiments, which are already funded, will focus on picking the right crew members.