NASA’s Year-Long Mars Simulation Is a Test of Mental Mettle

Four people will cohabitate in a small prototype Martian dwelling, mimicking the isolation and stresses of life on the Red Planet.
Chapea stimulation surrounded by mars surface textures
Illustration: WIRED Staff; NASA, Getty Images

On June 25, four crew members will suit up and embark on a Mars mission, living for an entire year in a small 3D-printed habitat with only each other for company. But these space explorers won’t leave Earth. Their simulated Martian environment is contained in a large hangar at NASA’s Johnson Space Center in Houston, and it’s designed to test the psychological and social challenges that will confront early visitors to the Red Planet, where remoteness and the harsh terrain will make life formidable

The program is called Chapea, which stands for Crew Health and Performance Exploration Analog. NASA hopes that lessons from this unique social experiment could aid future astronauts when they really do set foot on the ruddy Martian dirt—such as learning how the space agency can make the crew comfortable and help them get along with each other, or deal with loneliness or homesickness. “If we get to the end of the year and the crew is complete and we haven’t had any attrition, that would be, for me, a huge thing. It sounds doable, but it actually will be very hard,” says Kelly Haston, the mission’s biomedical researcher and commander. “We know we can actually leave. We’re volunteers, so there is an exit sign. On Mars you won’t have that.” 

Just like the first batch of Martian astronauts, Haston and her crewmates—Ross Brockwell, Nathan Jones, and Alyssa Shannon—will live in a cramped space without contact with other people. They’ll be able to communicate with mission control, but with a 20-minute delay, as if they were in fact some 100 million miles away from home. Like real visitors to Mars, they’ll see only a stark, lifeless landscape, which NASA is simulating with an enclosed space covered with Martian mural images and a 1,200-square-foot sandbox filled with red sand. Each week, they will have multiple opportunities to go outside for “Mars walks”—while wearing spacesuits. 

The 1,700-square-foot structure they’ll live in has been 3D-printed using a simulated Martian regolith to mimic NASA’s plans for future missions. It has Ikea-like furniture, clean spaces, and bright lighting, like a high-end hostel for space workers. The habitat includes small individual crew quarters, a communal space with a table for team dinners and meetings, chairs and a couch, a work area, a kitchen, two bathrooms, and an exercise room. And that’s about it. “The objective of the Chapea mission is to collect data on the crew’s health and performance while they are living in a realistically restricted environment and living the lifestyle that could be expected of Mars astronauts,” says deputy project manager Raina MacLeod.


While the idea of throwing four people into a single structure for a long time and seeing how they fare sounds kind of like a reality TV show, the crew will be disciplined, and they’ll have tasks to complete. In many ways, their day-to-day life will be similar to that of astronauts aboard the International Space Station, just with a bit more space and no floating. (People will feel lighter and bouncier on Mars, which is smaller and less massive than Earth, but that’s hard to simulate.) During the crew’s work hours, they’ll conduct mission operations, like the “Mars walks,” growing plants, getting exercise, cleaning the habitat, and maintaining equipment. The kitchen’s equipped with a small oven and a fridge, and they’ll have to rely on reconstituted dehydrated food between limited batches of fresh food delivered by infrequent cargo resupply missions. Their bathrooms have a shower, toilet, and sink with running water—a big improvement over life in microgravity—though the water for each crew member will be rationed, as there will be very limited water available on Mars.

NASA will be monitoring the Chapea crew using cameras posted inside the habitat, and someone will be available to them 24/7 at mission control. Like astronauts in Earth orbit, the crew will have private conferences with medical professionals to keep tabs on their mental and physical health, and those will be the only communications not subject to the usual time delay. They will also fill out surveys regarding their mood and temperament. The crew will be able to stay in touch with friends and family—but while they can send and receive video messages and emails, real-time conversations with them will be impossible.

While the accommodations look nice, the relative isolation might affect crew members over time, and it’s important to see how they fare. “NASA is right to study this, because what we’ve learned is that social isolation is a very dangerous psychological toxin,” says Craig Haney, a UC Santa Cruz psychologist who researches solitary confinement. Haney has documented the debilitating and sometimes permanent effects of isolation on prisoners—effects that can emerge in just a couple weeks. The situations aren’t the same, of course: While the Chapea bedrooms are similar in size to a solitary confinement cell, the crew also has other spaces for activities—and they have each other. They’ll still be more isolated than normal, however, like many of us were during the early days of Covid-19. During Covid “we’ve been denied the normal social interactions that we’ve learned to depend on. For many people, it’s proven to be extremely stressful, and it has generated forms of psychological maladies that were unanticipated at the outset of the pandemic,” he says.


With the Mars simulation, Haney suggests that NASA should watch the crew for danger signs, like symptoms of depression, heightened irritability, and moodiness, and changes in sleeping and eating patterns. And for the crew, he recommends creating routines, including social rituals, and trying to reach out to the outside world, not just to NASA’s mission control, to lessen the feelings of isolation.

For her part, Haston plans to bring along videos of familiar places and audio recordings of sounds and music that have meaning for her, anticipating the unsettling lack of sound in the simulated Mars environment. She also plans on using meditation to deal with anxiety. 

Chapea builds on previous Mars-like experiments, including the NASA-funded Hi-SEAS simulation on the northern slope of the Mauna Loa volcano in Hawaii. Hi-SEAS ran six experiments between 2013 and 2018, with the last one aborted after just four days when a crew member had to be taken to a hospital after suffering an electric shock. 

Kate Greene, author of Once Upon a Time I Lived on Mars, was in the first Hi-SEAS crew, which lived in the habitat for four months. (One of her crewmates was Sian Proctor, a geoscientist and artist who later flew in orbit on SpaceX’s Inspiration4.) Greene thinks these programs are useful. “What makes them worthwhile is thoughtful experimental design,” she says. “I think it is of the utmost importance to consider the human factors involved in a long-duration space mission. As Kim Binsted, the head of Hi-SEAS, often said, ‘If something goes wrong psychologically or sociologically with the crew, it can be as disastrous as if a rocket exploded.’”

Ashley Kowalski, who served on an eight-month US-Russian Mars simulation called SIRIUS-21, says they are also good for helping future crews psychologically prepare in advance. “Until you’re in that type of environment, you don’t really know how you’ll react to issues and situations that come up,” she says.

Ultimately, a real Mars mission will be much tougher than any simulation on Earth. Those astronauts will have to worry about threats like space radiation, the health effects of microgravity, and running out of water, food, power, and breathable air. And unlike the Chapea volunteers, if they get sick of their crewmates, they can’t just quit. 

But Haston points out the positive side of this unique situation too. “There’s the negative people bring up: ‘You’re going to be four people getting on each other’s nerves.’ But we’re also going to become a tremendous unit that can do things and understand each other in a way that most people don’t have in their workplace,” she says. “You’ll be so dependent on each other, and also so close to each other. Seeing that outcome will be amazing.”

Update 6-5-2023 7:00 PM: This story was updated to correct the nationalities of the agencies that ran the SIRIUS-21 program.