There are three men and three women participating in this second HI-SEAS mission—a purposely tiny group selected out of a group of 700 applicants—and they include, among others, a neuropsychologist, an aerospace engineer, and an Air Force veteran who is studying human factors in aviation. The team will share a 1,000-square-foot habitat that is shaped like a dome. They will do so ... for four months. (Consider that for a second: living with five other people—strangers. For four months. In what amounts to a high-tech yurt.)

“We’re going to stress them,” Kim Binsted, the project’s principal investigator, told the Hawaii Tribune-Herald. “That’s the nature of the study.”

Indeed. That test involves isolating the crew in the same way they'd be isolated on Mars. The only communication they'll be allowed with the outside world—that is to say, with their family and friends—will be conducted through email. (And that will be given an artificial delay of 20 minutes to simulate the lag involved in Mars-to-Earth communications.) If that doesn't seem too stressful, here's another source of stress: Each mission member will get only eight minutes of shower time ... per week. The stressfulness of which will be compounded by the fact that the only time the crew will be able to leave their habitat-yurt is when they're wearing puffy, insulated uniforms that simulate space suits. In the Hawaiian heat.

Throughout the mission, researchers will be testing the subjects' moods and the changes they exhibit in their relationships with each other. They'll also be examining the crew members' cognitive skills, seeing whether—and how—they change as the experiment wears on.

The crew, at the same time, will be executing other projects that are relevant to life on Mars—including the testing of 3D-printed surgical tools, the growing of plants in Martian-like conditions, and, perhaps least stressfully, the repurposing of trash into tools that can be put to use in the Martian habitat. They'll also be doing projects outside of the habitat, in their "space suits"—like mapping nearby lava flows—to test their ability to work together under Martian conditions. (All this work, by the way, is a follow-up to HISEAS' previous experiment, from 2013, whose participants tried to make Martian meals that would be palatable to future colonists.)

So why does NASA care how these six humans react to an experience that amounts to pretty much the worst Hawaiian vacation ever? Because a manned mission to Mars is a priority for NASA; though funding for such a project remains in question post-sequestration, the agency still hopes to establish a Martian mission that would launch in the 2030s. And it needs to make sure that the humans it sends on that mission are equipped for the many challenges it will present—not just technologically, but emotionally.

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