Bill Stafford/NASA
CHAPEA -- Crew Health and Performance Exploration Analog -- is the latest series of Mars analog missions conducted by NASA. A simulation of life on the Martian surface, each of the three planned missions will last 378 days, and take place in a sealed habitat inside the Johnson Space Center in Houston, Texas. Scroll through the gallery to explore the CHAPEA habitat and see Mars analogs around the world.
Bill Stafford/NASA
The CHAPEA base was designed in collaboration with Bjarke Ingels Group and 3D-printing company ICON, who build the habitat with layers of concrete mixture dubbed "lavacrete." Robotic 3D-printing is one way humans might be able to create a viable base on Mars.
Bill Stafford/NASA
The habitat is 1,700 square feet and includes work stations, living and kitchen area, medical center, as well as bathroom and private bedrooms. "The separation of the living area with the work area was very intentional," says Scott M. Smith, co-investigator for CHAPEA.
Bill Stafford/NASA
The habitat also includes an exercise area. The four participants shut in the base will simulate space-relevant activities, including maintenance and repairs, and will be rigorously tested for the impact of confinement and diet on both their physical and mental health.
ICON
The structure for the base was built in a hangar at the Johnson Space Center in approximately a month by ICON's robotic printer Vulcan.
ICON
The walls of the base being printed in 2021. The ceiling was printed separately and moved into place.
Jack Guez/AFP/Getty Images
CHAPEA is one of many analog space missions taking place around the world. Others are exploring ways to overcome the challenges of sending humans to Mars, like AMADEE-20 (pictured), a simulation led by the Austrian Space Forum, involving six astronauts who spent a month cut off in Israel's Negev desert in 2021
Oleg Voloshin/AFP/Getty Images
One of the most cited Mars analogs is Mars-500, a series of three simulations that ran between 2007 and 2011, culminating in a 520-day mission to Mars that simulated the flight there and back, descent and landing, and research time on the surface.
NASA
NASA's HERA (Human Exploration Research Analog) program utilizes a 650-square foot habitat inside the Johnson Space Center. The unit is designed to reflect a spacecraft and used for confinement and isolation simulations. There have been six missions so far, with the latest starting in January 2023 and running for 45 days, simulating at trip to Phobos, one of Mars' moons. Crews are tested for health, behavior and performance.
NASA
NASA's Desert Research and Technology Studies (Desert RATS) program has tested a number of rovers and mobility equipment, as well as modules such as the Deep Space Habitat's GeoLab (pictured, 2011) at Black Point Lava Flow, Arizona.
Bill Stafford/NASA
Another Desert RATS mission is a partnership between NASA and JAXA -- the Japan Aerospace Exploration Agency -- that is testing living, working and sleeping inside a rover in a simulation for moon surface missions as part of the Artemis program.
NASA
The SIRIUS (Scientific International Research In a Unique terrestrial Station) confinement and isolation experiments have taken place in the Nazemnyy Eksperimental'nyy Kompleks, or NEK, facility in Moscow, Russia. The facility was built in the 1960s and has been used in many analogs, including Mars-500. In the past, SIRIUS missions have involved participants from the US and Russia.
NASA
Not all analogs involve finding a place that looks like Mars. Bed rest studies like :envihab, a 60-day project conducted by NASA, the ESA and the German Space Agency (DLR) in 2019, have used bed rest to simulate some of the effects of microgravity, and tested whether stints in a centrifuge like the one pictured can alleviate some of its impact.
AFP/AFP/AFP via Getty Images
Concordia Station, a French-Italian research base in Antarctica, is known as "White Mars" due to its hostile climate and extreme isolation. Crew on the International Space Station are closer to the nearest humans than the inhabitants of Concordia, where temperatures can drop to -80 Celsius. It experiences near total darkness for roughly four months of the year, and the small winter crew is tested by the European Space Agency to determine the psychological and physiological impact of the environment.

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For anyone who has ever dreamed of living on Mars, NASA is seeking potential “Martians” for a simulated mission to the red planet.

The space agency has put out a call for applicants to its second planned CHAPEA, or Crew Health and Performance Exploration Analog, mission, which will begin in the spring of 2025.

For one year, a volunteer crew made up of four people will live and work inside Mars Dune Alpha at NASA’s Johnson Space Center in Houston. The 3D-printed habitat, spanning 1,700 square feet, is designed to resemble the living conditions of a crew of astronauts that will land on the Martian surface in the future.

Understanding how a crew reacts to the challenges of a deep space mission is essential for planning how astronauts will explore the red planet.

Inside Mars Dune Alpha, participants will grow crops, maintain their habitat, exercise, carry out robotic operations and go on simulated spacewalks. And they will face real issues such as equipment failure, communication delays, environmental stressors and dealing with limited resources.

The application process is now open and will close on April 2, according to the agency.

NASA’s crew criteria

The CHAPEA program is looking for nonsmoking, healthy US citizens between the ages of 30 and 55 years old who are proficient in the English language.

“Applicants should have a strong desire for unique, rewarding adventures and interest in contributing to NASA’s work to prepare for the first human journey to Mars,” according to the agency.

When it comes to selecting the CHAPEA crew, the agency has specific criteria in mind that aligns with how they select astronauts.

NASA
NASA astronaut and Expedition 68 Flight Engineer Josh Cassada is pictured bundled up in his crew quarters aboard the International Space Station.

Sleeping will be one of the challenges for astronauts on Mars missions

The Mars simulated crew members need a master’s degree in a STEM field, such as engineering, mathematics, or biological, computer or physical science, or a related requirement like a medical degree, and must be able to pass the astronaut physical test. They also need two years of professional experience within their chosen field or at least 1,000 hours of pilot-in-command time on a jet aircraft.

The selection process timeline could take up to 13 months, and finalists will need to undergo medical, psychological and psychiatric tests to make sure they are mentally and physically suited for such a long and isolating mission.

NASA
Inside the habitat, the CHAPEA 1 crew conducts "Marswalks" (left) and grows crops using a system with appropriate lighting, water and nutrients for growing plants indoors.

And be sure to read the fine print: Food allergies or certain medications could cause applicants to be disqualified. While being screened, candidates can find out how they will be compensated for their time if selected.

A series of Mars simulations

The first CHAPEA mission, which began on June 25, 2023, is set to conclude on July 6. The main goals of the first mission have been monitoring and assessing the health and performance of the crew as they live in a confined space while dealing with the anticipated challenges of life on Mars.

The crew includes research scientist Kelly Haston, structural engineer Ross Brockwell, emergency medicine physician Nathan Jones and microbiologist Anca Selariu.

NASA/Getty Images North America/Getty Images
IN SPACE - DECEMBER 21: In this handout photo provided by NASA, NASA astronaut Scott Kelly is seen floating during a spacewalk on December 21, 2015 in space. NASA astronauts Scott Kelly and Tim Kopra released brake handles on crew equipment carts on either side of the space stations mobile transporter rail car so it could be latched in place ahead of Wednesdays docking of a Russian cargo resupply spacecraft. Kelly and Kopra also tackled several get-ahead tasks during their three hour, 16 minute spacewalk. (Photo by NASA via Getty Images)

Astronauts face mental and emotional challenges for deep space travel. Scientists are working on solutions

So far during their time in isolation, the crew has harvested their first crops, including leafy greens, peppers and tomatoes, using an indoor home gardening system. The team has also gone on numerous simulated “Marswalks” in a 1,200-square-foot red sandbox designed to mimic what it might be like to go on excursions on the Martian surface. And the crew continues to carry out biological and physical experiments and investigations.

Josh Valcarcel/NASA
The CHAPEA Mission 1 crew, including Nathan Jones, Ross Brockwell, Kelly Haston, Anca Selariu (from left to right), is pictured on June 26, 2023, before entering the habitat.

The lessons learned from the inaugural CHAPEA mission will help NASA fill knowledge gaps about how to make sure Martian crews are healthy and have adequate supplies and support while living millions of miles away from Earth. Three total CHAPEA missions are planned, and all have similar goals.

“The second mission will be pretty similar to the first mission with the same goals in order to gather additional data across participants,” said Anna Schneider, public affairs officer at Johnson Space Center.