Four people leave a fake Mars after 378 days. The planet was never the point.
NASA's second year-long Mars simulation has ended in Houston. It tested what a long stay in a small room does to a crew, and it left the rest of Mars alone.
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Nov 2, 12:00 UTC ·
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Four volunteers walked out of a 3D-printed habitat in Houston on October 31, 2026, ending 378 days of simulated Mars living that tested people, not hardware. [1][3]
The crew was mission commander Ross Elder, medical officer Ellen Ellis, science officer Matthew Montgomery and flight engineer James Spicer. [1][5] They went in on October 19, 2025, at NASA's Johnson Space Center. [3] The exit and the crew's first remarks come from a Reuters report carried by CGTN, the Chinese state broadcaster, and NASA has not yet published any results from the year. [1]
A year in 1,700 square feet
The mission is called CHAPEA. An analog is a stand-in on Earth for a place you cannot yet go, and this one is a rehearsal, not a trip. NASA runs a series of year-long stays in an isolated habitat to learn how people cope with confinement, limited resources and mission routines. [2][5]
The first crew finished a similar 378-day stay on July 6, 2024, after starting on June 25, 2023. [2][5] This was the second.
The habitat measures 1,700 square feet. [3] Four people, 378 days, 1,700 square feet. Inside it, the crew grew crops, maintained the habitat, ran robotic operations and carried out simulated spacewalks on a mock Martian surface. [1][3][4]
At the 200-day mark, Spicer described the work as simulated spacewalks, geology, exercise and medical activities. [4] Montgomery said limited tools, equipment, software, supplies and internet forced the crew to find solutions with what it had. [4] Nobody was going to send a part.
The calendar was the hard part
Real Mars missions will not allow a quick call home, so neither did this one. NASA said messages could take up to 45 minutes each way, which makes a round trip of up to 90 minutes for a single question and its answer. [3][4] The crew wrote to family by email, with the same Mars-like delay. [3]
At one point NASA also ran a simulated two-week communications blackout. The crew worked from preplanned procedures and whatever resources it had, with no contact with mission control. [4] What happened during those two weeks has not been described publicly.
What the crew said
Ellis summed up the year for the cameras. It was, she said, "a hell of a year," and the four were "analog astronauts living in captivity of our own free will." [1]
She said the crew had dealt with limited resources, kept the habitat running and carried out simulated Mars operations. [1] Vanessa Wyche, director of NASA Johnson, said the delayed communications called for patience, careful planning and greater independence. [1]
That last word is the heart of the exercise. A crew months from Earth cannot wait an hour and a half to settle every question, so it has to decide for itself. NASA says the mission's data may help it judge how food and exercise systems affect mission goals, and how to support crew autonomy and decision-making when contact is delayed. [3]
What a box in Houston cannot do
The crew never left Houston, and NASA is plain about what that means. CHAPEA does not recreate every condition of spaceflight. The agency's wider human research also draws on laboratories, commercial missions, the International Space Station and Artemis missions. [3][4] Each of those answers a different question, and this one asks about the people.
The hardest part of a Mars mission may be the one no bigger rocket can fix. Engineers can calculate thrust. They cannot calculate how four people hold together over a year with the same few faces and the same few rooms, so NASA runs the experiment, one crew at a time.
That is also the limit of the result. Two crews of four are a thin sample. Mission 2 adds a second case to the first, and it does not settle how every future crew will cope. [2][3]
The questions most readers will ask first are still open. What did the crew eat, and do the four still like each other? The exit coverage does not say.
What comes next
The crew now faces two weeks of health and performance evaluations and debriefs with NASA scientists, and a reunion with family. [1][3] The debriefs may matter as much as the measurements. A year in a box leaves a crew with knowledge no sensor records, such as what grated, what helped and what the schedule got wrong.
The agency says it will use the data to plan how to keep future crews healthy, productive and able to work on their own. [1][3] The first findings from those evaluations are the next thing to watch for.
Our call
NASA will publish on nasa.gov an article, report or paper giving at least one specific health or performance finding from CHAPEA Mission 2, beyond the schedule of evaluations.
NASA has said the post-mission evaluations last two weeks and that the data will inform future planning, but nothing in the record gives a publication date for results.
Elena MarshElena MarshSenior writerWrites the long pieces that make people read to the end. Believes every story is a history story if you go back far enough, and usually goes back just far enough.Model: Claude Sonnet 5.5 says
25%. Jev says 39%.
By January 31, 2027. How we will check: Search nasa.gov and NASA's research publication listings for CHAPEA Mission 2 material published between November 9, 2026 and January 31, 2027 that reports a concrete result from the crew's data or debriefs, such as a measured outcome or a named lesson. A post that only describes the evaluations or repeats the exit does not count.
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- NASA's simulated Mars mission crew emerges after 378 days in isolation - CGTN CGTN Tech & Science (Chinese state broadcaster)
- CHAPEA - NASA nasa.gov
- NASA's Simulated Mars Crew Marks One Year Inside Habitat - NASA nasa.gov
- NASA's Simulated Mars Mission Marks 200 Days Inside Habitat - NASA nasa.gov
- NASA Announces CHAPEA Crew for Year-Long Mars Mission Simulation - NASA nasa.gov