Forming a band and growing crops: What a year in a simulated Mars mission is really like

Four people have spent 378 days seeing what it would be like to live on Mars...without leaving Earth.

The crew members took part in a simulated mission to the Red Planet, spending just under a year in isolation at Nasa's Johnson Space Center in Houston.

It's Nasa's second Crew Health and Performance Exploration Analog, or CHAPEA, mission. The first ended in July 2024.

The exercise is meant to prepare astronauts for future trips to Mars.

The astronauts live in a specially designed habitat.

It's a 1,700-square-foot (158-square-metre), 3D-printed structure with four bedrooms, a dining/living area, a workspace with a vertical farm to grow things and a medical room.

The experience is meant to simulate what living on Mars may be like, and that includes things like isolation and equipment failure.

Activities during the year included growing crops, science experiments, simulated space walks, meal preparation and dealing with problems like a two-week loss of communication.

The crew recorded a podcast during their year and, in their final episode, talked about things that may surprise people about their experience.

1. Everything they consumed has to be logged.

"Every sip of water, every shake of the salt shaker goes to Nasa, so they can see how what goes in affects our performance," said James Spicer.

2. It's very quiet.

Ross Elder, commander of the CHAPEA Mission 2 crew, called it "eerily quiet" with only noises from fans and equipment.

"I actually miss the sound of weather, busy streets, and just like commotion in general. So much that I tend to listen to music and movies and recordings, and the crew sees me all the time with my earbud in, just so I have some kind of noise to fill the silence."

3. They use a lot of tools, but they might not be the ones you expect.

Flight engineer James Spicer says they use a wide range alongside tools like wrenches.

"We had to get our drain snake the other day to clear some plumbing issues. We had to use a metal detector the other day. I had to break out a needle and thread to sew up a large hole in my flight suit."

4. They formed a band.

The crew brought some instruments along and have been practicing in their downtime as Ross Elder explained.

"Since we're a bit limited on our instrument selection, and we're definitely still looking for the right set list, but I think we found a few things here or there that sounded pretty decent. It's a start."

The crew left the habitat on Saturday 31 October and were met by Vanessa Wyche, director of the Johnson Space Center.

She praised how the team coped with the conditions and said the lessons learnt from the exercise will help pave the way for the missions first ​to the Moon and "one day, Mars."

The four will now be reunited with friends and family who they've only spoken to via email for a year.