A Year on ‘Mars’ Without Leaving Houston: What NASA’s CHAPEA Crew Is Teaching Us About the Red Planet

Quick answer: On 19 October 2026, the four volunteers of NASA’s CHAPEA Mission 2 completed a full year inside a sealed, 3D-printed “Mars” habitat at the Johnson Space Center in Houston. Commander Ross Elder, medical officer Ellen Ellis, science officer Matthew Montgomery and flight engineer James Spicer have been living as if they were on the Red Planet since 19 October 2025, with limited supplies, a Mars-like communication delay, home-grown crops and simulated “Marswalks.” Their 378-day mission ends when they walk out on Saturday, 31 October. The data they produce will help NASA work out how to keep real crews healthy and productive on the first human missions to Mars.

Nobody has left Earth, yet for a year four people have lived with many of the constraints of a Mars mission: fixed food stocks, email-only contact with family, equipment that breaks, and an outside world they can only reach through an airlock and a spacesuit. Here is what the experiment is, what life inside looks like and why NASA thinks it matters.

What is CHAPEA?

CHAPEA stands for Crew Health and Performance Exploration Analog. According to NASA, it is a series of Earth-based missions that simulate year-long stays on the surface of Mars. Each mission puts four crew members in an isolated 1,700-square-foot (about 160 m²) habitat, where they carry out simulated spacewalks and provide data on their physical and behavioural health and performance.

The programme is run by NASA’s Human Research Program. Its stated goal is practical: NASA says the results will help it characterise the risk of its planned exploration food system for crew health and performance, and inform its standards, vehicle mass and volume requirements, and the trade-offs between resources and risk on long missions.

Why simulate Mars on Earth?

On a real Mars mission there is no quick return and no regular resupply. NASA notes that food for a Mars crew would likely be sent ahead of time, leaving no way to deliver fresh fruit and vegetables or tailor menus for individual astronauts, both of which are standard on resupply flights to the International Space Station. A ground analog lets scientists study those constraints over a full year in a controlled setting, with doctors and engineers close by.

Inside the 3D-printed habitat

The habitat, called Mars Dune Alpha, was printed by the construction-technology company ICON using its Vulcan construction system and a material called “lavacrete,” according to NASA’s habitat page. The agency explains the choice of 3D printing directly: future settlements could be built with additive construction to avoid launching large quantities of building materials on multiple flights, which would be prohibitively expensive.

Inside, the layout separates living and working areas. NASA lists:

• Four private crew quarters and two bathrooms
• A kitchen (galley) and food-growing stations
• Dedicated workstations and a medical station
• Common lounge, recreation and fitness areas
• A technical work area

Attached to the habitat is a 1,200-square-foot sandbox filled with red sand to stand in for the Martian landscape, shown in the featured image above. That is where the crew go on “Marswalks.” Even then, they never actually leave: NASA says the crew put on spacesuits and step into the simulated Mars environment directly outside the habitat, but stay isolated inside the building that houses CHAPEA.

Who is the Mission 2 crew?

NASA introduced the four volunteers when it announced the crew in 2025:

• Ross Elder, commander: a major and experimental test pilot in the US Air Force who has flown more than 35 military aircraft.
• Ellen Ellis, medical officer: a colonel and acquisitions officer in the US Space Force, and a former intercontinental ballistic missile operations officer and GPS satellite engineer.
• Matthew Montgomery, science officer: a hardware engineering design consultant whose work includes LED lighting, robotics and controlled-environment agriculture.
• James Spicer, flight engineer: a technical director in the aerospace and defence industry with experience building satellite communications networks and space data relay networks for human spaceflight.

Emily Phillips, a US Marine Corps captain and F/A-18 pilot, and Laura Marie, a commercial airline pilot, served as alternate crew members.

What a year on “Mars” looks like

NASA’s one-year update sums up the routine: for 365 days the crew have operated as though they were on the Red Planet, growing crops, managing limited resources, navigating communication delays and conducting suited extravehicular activities on a simulated Martian surface. They have spoken to their families only by email, with a Mars-like delay.

The communication delay

Radio signals between Earth and Mars travel at the speed of light, but the distance means messages still take minutes to arrive. CHAPEA builds that in. NASA describes 22-minute communication delays for Mission 2, and for Mission 1 it described Mars-realistic delays of up to 44 minutes round trip. That rules out live conversations with Mission Control, so the crew have to solve many problems on their own.

Food, crops and fitness

The food system combines prepackaged, shelf-stable food with crops the crew grow themselves. NASA’s crop production lead for CHAPEA, Gioia Massa, has said that salad crops “may supplement the packaged meals, reduce menu fatigue, and provide a creative outlet,” and may also offer psychological benefits for people living in isolation. NASA’s Mission 2 photo log shows peppers and other vegetables thriving in the habitat’s hydroponic system, along with regular exercise sessions and fitness tests in which a mask tracks how well a crew member’s body uses oxygen.

Medicine and maintenance

The crew also act as their own clinic and repair team. NASA’s photos show them collecting blood samples to monitor their health, testing a medical monitoring device that measures blood pressure and other markers, and demonstrating an artificial-intelligence-enabled medical training system. When it announced the crew, NASA said technologies designed for deep space, including a potable water dispenser and diagnostic medical equipment, would be tested during the year.

What NASA hopes to learn

According to NASA, the data could show how limited food and exercise systems affect a crew’s ability to achieve mission goals, including spacewalks on the surface of Mars. Some of it could also help NASA build decision-making support systems for crews that cannot get quick answers from Earth.

“We are extremely proud of the crew for their commitment and achievements over the last year on such a fast-paced, highly demanding mission,” said Grace Douglas, CHAPEA’s principal investigator. Michael Stenger, chief scientist for NASA’s Human Research Program, said the 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.”

After they exit on 31 October, the crew will spend two weeks on post-mission evaluations and debriefs with NASA scientists. NASA plans to stream the egress ceremony live on YouTube.

The first CHAPEA mission and what came before

Mission 2 follows CHAPEA Mission 1, which ran in the same habitat from 25 June 2023 to 6 July 2024 with commander Kelly Haston, flight engineer Ross Brockwell, medical officer Nathan Jones and science officer Anca Selariu. When that crew came out, NASA said two more one-year missions were planned and would be nearly identical, so researchers could collect data from more people and build a broader picture.

CHAPEA is not the first long Mars simulation. The best-known earlier study, Mars500, a joint project of ESA and Russia’s Institute for Biomedical Problems (IBMP) in Moscow, kept six male volunteers in a 550 m³ chamber for 520 days. It ended on 4 November 2011, according to the European Space Agency. The results showed why this kind of research matters:

• A 2014 study in PLOS ONE found large differences in how individual crew members coped. Conflicts with mission control were reported five times more often than conflicts among crew members. One volunteer developed persistent insomnia, while two showed no behavioural disturbances or psychological distress over the 17 months.
• Another PLOS ONE study found that the crew’s physical activity fell progressively during isolation, with greater declines in leg performance than in arm strength. The authors concluded that prolonged confinement acts as a form of physical inactivity.

CHAPEA’s emphasis is different: it is built around a Mars-realistic, restricted food system, crop growth and high-tempo Marswalks on a simulated surface, and it is being repeated with several crews in the same habitat.

Want more from beyond Earth? Read about 14 Herculis c, one of the coldest exoplanets ever imaged by Webb, the discovery of the first “green star”, and how astronomers linked a supernova seen in 1181 to its strange remnant. More stories are in our Science section.

Frequently asked questions

What is NASA’s CHAPEA mission?

CHAPEA (Crew Health and Performance Exploration Analog) is a series of year-long simulated Mars surface missions at NASA’s Johnson Space Center in Houston. Four volunteers live in a 1,700-square-foot 3D-printed habitat while NASA studies their health and performance.

When does CHAPEA Mission 2 end?

The crew entered the habitat on 19 October 2025 for a 378-day mission and are scheduled to exit on Saturday, 31 October 2026, followed by two weeks of evaluations and debriefs.

Who is on the CHAPEA Mission 2 crew?

Ross Elder (commander), Ellen Ellis (medical officer), Matthew Montgomery (science officer) and James Spicer (flight engineer). Emily Phillips and Laura Marie were the alternates.

Why is the CHAPEA habitat 3D printed?

NASA says future settlements on other worlds could be 3D printed to avoid launching large quantities of building materials on multiple flights, which would be very expensive. The habitat was printed by ICON with a material called lavacrete.

How long does a message take to reach Mars?

It depends on where the planets are in their orbits. CHAPEA Mission 2 uses communication delays of 22 minutes, and NASA has described Mars-realistic delays of up to 44 minutes round trip.

Sources: NASA (one-year update); NASA (crew announcement); NASA (mission start); NASA (habitat); NASA (food systems); ESA; Basner et al., PLOS ONE (2014); Belavý et al., PLOS ONE (2013).

Featured image: the simulated Martian surface inside NASA’s CHAPEA facility, by NASA/Bill Stafford, public domain, via Wikimedia Commons.