Summary:
Four research volunteers marked a full year inside NASA's Mars Dune Alpha habitat on 19 October 2026 and are due to exit on 31 October, after 378 days. The habitat is a 3D-printed simulation of a Martian base at the Johnson Space Center, NASA's astronaut training and mission-control centre in Houston. Its occupants are Ross Elder, the commander and an Air Force test pilot; Ellen Ellis, the medical officer and a Space Force colonel; Matthew Montgomery, the science officer and an engineer; and James Spicer, the flight engineer and a satellite-communications specialist.
They are paid study participants rather than astronauts. The mission, the second in NASA's Crew Health and Performance Exploration Analog, or CHAPEA, a ground-based stand-in for spaceflight, is built to measure how people perform when isolated, confined and short of supplies. To that end the crew grow what fresh food they eat, talk to a mission control whose messages take up to 22 minutes each way, go dark for days at a time to simulate the Sun blocking Mars from Earth, and repair equipment failures that NASA stages for them.
NASA says the findings are meant first for the Moon and later for Mars, since sustained work on the lunar surface is the nearer goal and raises the same problems of housing, feeding and performance far from help. It has not published results from this mission or from the first, which ran the same 378 days between June 2023 and July 2024.
Detailed Report
1. Inside Mars Dune Alpha: How Four People Have Lived for a Year
The four entered the habitat on 19 October 2025 from careers in military aviation, space operations and engineering.
Mars Dune Alpha is a single-storey structure of 1,700 square feet, or about 158 square metres, printed in 2021 from concrete dyed to approximate the reddish tones of Martian soil. Its layout runs as a gradient of privacy, with four private quarters at the south end, shared living areas in the middle, and the work, medical and crop zones beyond them.
The only way out is an airlock that opens onto a red-sand yard of about 1,200 square feet, or roughly 110 square metres, where the crew perform Marswalks, simulated surface excursions in which they wear spacesuits and collect geological samples. Those excursions sit alongside robotic operations, equipment maintenance, exercise, glovebox experiments on samples and regular medical monitoring that includes blood collections.
Three constraints test that routine. Food is the first: the crew rely on shelf-stable meals and on the leafy crops, herbs and small fruits they raise themselves in an indoor growing system. NASA adds the second by staging simulated equipment failures, which the crew must work through with what the habitat holds. The third is distance: a message takes five to 22 minutes to cross, so a question and its answer can sit 44 minutes apart, and for days at a time the signal drops out entirely to simulate solar conjunction, when the Sun lies between Earth and Mars. Family contact has been by delayed email alone.
Montgomery put the effect of those limits in engineering terms at the 200-day mark, in a NASA article published on 7 May 2026:
"Having limited resources, be it tools, equipment, software, supplies, or no internet, really bounds what you have to solve problems. Finding creative and clever solutions has been both challenging and rewarding."
2. Measuring Isolation: What the Study Is Designed to Produce
NASA says the year serves three purposes: to collect cognitive and physical performance data from people working under restricted resources and long isolation, to measure the risk the planned exploration food system poses to crew health and performance, and to inform habitat design, vehicle mass and volume, and resource trade-offs on long missions to the Moon and Mars. It also wants to learn what medical and psychological care, autonomy and decision-making demand when messages take time to cross.
The simulation cannot reproduce Martian gravity, which is about 38% of Earth's. The habitat sits under Earth's full gravity, so the physiological effects of reduced gravity go unmeasured; what the analog isolates is the human and logistical side of a Mars year — confinement, scarcity and distance.
Michael Stenger, chief scientist for NASA's Human Research Program, which studies the health and performance risks of spaceflight, said the year had already changed what NASA understands about long missions:
"This mission has been incredibly valuable in starting to teach us how to understand requirements for year-long missions, including medical and psychological care, via communication delays. When combining this Mars-realistic mission analog with a suite of physiological, psychological, and performance measures in a rigorously controlled environment, we'll be able to translate the knowledge from these experiences to Moon Base and beyond."
The reference to a Moon base follows the order of NASA's plans. A crewed Mars mission is the long-term goal, but the nearer effort is NASA's lunar planning, which includes a sustained outpost at the lunar South Pole, and that outpost would face the problems the habitat was built to test: housing a crew, feeding it without resupply and keeping it performing when cut off.
3. From CHAPEA to MMEA: The Next Year-Long Simulation
The crew's exit on 31 October will be followed by two weeks of post-mission evaluations and debriefs. Analysis of both missions' data is continuing, and NASA has published no crop yields, cognitive scores, medical findings or resource-consumption figures from either, while keeping the specifics of the crews' tasks confidential to preserve surprise for later crews.
The research then moves into a larger format. In early July 2026 NASA unveiled the Moon and Mars Exploration Analog, or MMEA, the first ground-based simulation to join a spacecraft transit and a stay on the surface in one continuous year. NASA says it "evolves elements of the agency's HERA and CHAPEA missions into a single, integrated mission," and it begins no earlier than August 2027.
The transit phase would run in an adapted version of HERA, the Human Exploration Research Analog, and the crew would then move into Mars Dune Alpha for the surface phase, where a rover able to house two people would carry them on multi-day excursions. NASA says the data would inform crew health and performance on Artemis, its programme to return astronauts to the Moon, and on eventual Mars missions.
Conclusion
Four volunteers have spent a year in a Houston habitat living as a Mars crew would, growing part of their own food, cut off from the outside world for days at a time and repairing failures NASA staged for them. NASA says what they learn is meant first for the Moon and then for Mars.