For the past four months, a team of researchers have been living in a mockup Mars habitat on a Hawaiian volcano practicing isolated living on the Red Planet.
For the most part, expedition leader Casey Stedman and his five crewmates have stayed inside their 1,000-square-foot solar-powered dome, venturing out only for simulated spacewalks and doing so only when fully attired in mock spacesuits.
"I haven't seen a tree, smelled the rain, heard a bird, or felt wind on my skin in four months," Stedman wrote in a blog on Instagram. Stedman is a U.S. Air Force Reserve officer, graduate student at Embry-Riddle Aeronautical University Worldwide.
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"We are simulating a long-duration mission on Mars, with a focus on crew psychology in isolation," the crew said during an online interview with Reddit on Sunday.
Crewmembers, who include a NASA chemical engineer and a neuropsychologist at the Fort Wayne Neurological Center in Indiana, have been isolated from direct human contact and have been eating dehydrated and shelf-stabilized foods.
"We've basically been subsisting on mush. Flavorful mush, but mush nonetheless," crewmember Ross Lockwood wrote on Instagram. Lockwood is finishing a doctorate in physics at the University of Alberta.
The habitat, which is outfitted with waterless composting toilets, is basically self-sustaining except for a water resupply and wastewater recovery every two- to three weeks.
Communications with the outside world have been time-delayed to match the 20-minute travel time of radio waves passing between Earth and Mars.
In addition to a battery of daily psychological surveys, the researchers tend to science projects and other studies, including expeditions outside the habitat to scout Mars-like features on Hawaii's Mauna Loa volcano. The landscape is similar to a region on Mars known as Tharsis.
For fun, there are movies, board games and exercise, Lockwood told Reddit.
"We don't have a lot of spare time, but I count work as part of the fun as well. Planning EVAs (spacewalks), preparing food, even chores - these are all enjoyable activities," he said.
The operational part of the Hawaii Space Exploration Analog and Simulation mission, known as Hi-SEAS 2, wraps up on Friday, but it will take months to synthesize all the findings.
The point of the project is to create guidelines for future missions to Mars, the long-term goal of the U.S. human space program.
"Hopefully, when we send humans to Mars, we will have done enough missions like HI-SEAS that we'll remember to bring the really important stuff, like extra toilet paper," mission support team member Gary Strawn said on Reddit.
The simulation, which is funded by NASA and overseen by the University of Hawaii, began on March 28.
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