Four “analog astronauts” are venturing on a simulated mission to Mars to help NASA scientists understand human dynamics on long-duration missions.

On Sunday, Kelly Haston, Ross Brockwell, Nathan Jones and Anca Selariu entered a mock Martian base at the U.S. space agency’s Johnson Space Center in Houston, where they will spend the next 12 months living like a crew of astronauts would on a deep space mission. 

As the first of three planned Crew Health and Performance Exploration Analog (CHAPEA) missions, the participants will be remotely observed by scientists as part of an effort to plan for future human missions on the real Martian surface. The crew will not leave their 1,700-square-foot habitat, called “Mars Dune Alpha,” until July 7, 2024.

CHAPEA is just one of many analog astronaut missions — each with varying timescales — that the agency uses to help plan for deep space missions. Mission 1 is a bit unique as this will be the first time crews are isolated for 378 days, only able to leave their habitat during planned Mars-walks that take place in an adjoining enclosure called the “Sandbox.”

The CHAPEA missions will add valuable data on how 12 different people interact and live together over an extended period in isolation. To be selected as part of the crew, the analog astronauts had to have a degree in a science, technology, engineering or mathematics discipline, as well as professional experience in their respective fields or military training — much like traditional NASA astronauts. They also had to pass the same physical and psychological testing as astronaut candidates.

Each crew member has an integral role to play: Haston, a research scientist, is the mission commander; Brockwell, a structural engineer, is flight engineer; Jones, an emergency medicine physician, is the medical officer; and Selariu, a microbiologist in the U.S. Navy, is the science officer.

Officials said this mission will focus on resource restriction and how the crew adjusts to challenges and scenarios that an actual crew on a Mars mission would face. This includes spaceflight food systems, time delayed communications and more. 

Crew members may also encounter some unexpected problems over the course of their mission to see how they might react, although what exactly those issues will be, officials haven’t said.