Four volunteers living inside a 1,700-square-foot 3D-printed habitat at Johnson Space Center reached 365 days in isolation on Monday, Oct. 19.

They still have 13 days to go.

Ross Elder, Ellen Ellis, Matthew Montgomery and James Spicer entered NASA's Crew Health and Performance Exploration Analog (CHAPEA) Mission 2 habitat on Oct. 19, 2025, and have been operating as though they were on Mars ever since. The full mission runs 378 days, with the crew scheduled to exit Saturday, Oct. 31, according to NASA.

The habitat sits at Johnson Space Center, just minutes from the Clear Lake community. For the crew inside, though, Earth might as well be millions of miles away. Their only contact with family has been email sent with a simulated Mars communication delay.

Elder serves as mission commander, Ellis as medical officer, Montgomery as science officer and Spicer as flight engineer. Over the past year, they have grown crops, managed limited resources and conducted simulated spacewalks on a mock Martian surface.

"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 principal investigator.

NASA said the data collected could help the agency understand how limited food and exercise systems affect mission objectives, including real spacewalks on Mars. It could also help NASA build decision-making support systems for crews dealing with communication delays lasting up to 45 minutes each way.

Michael Stenger, chief scientist for NASA's Human Research Program, said the mission has been valuable in beginning to teach the agency how to understand requirements for year-long missions, including medical and psychological care delivered through communication delays.

When the crew exits, they will reconnect with their families and begin two weeks of post-mission evaluations and debriefs with NASA scientists. Those sessions will help researchers learn what future explorers need to stay healthy and productive on long-duration missions far from Earth.

NASA plans to livestream the egress ceremony. The CHAPEA Mission 2 page has details on the mission and how to watch.

Coming up: CHAPEA Mission 2 egress ceremony, Saturday, Oct. 31, at Johnson Space Center. Livestream details at nasa.gov.