Four crew members involved in a Nasa experiment designed to test the human impact of a year-long Mars mission have finally emerged from their craft after 378 days inside.

The first of three Crew Health and Performance Exploration Analog (CHAPEA) missions began in June last year and was designed to test how humans could live and work on the Red Planet.

The mission was contained in a hangar at the Johnson Space Centre in Houston, Texas, and forced the participants to contend with limited resources, simulated equipment failures and a 22-minute delay in communications. Other activities include simulated spacewalks or ‘Marswalks’ outside the habitat – some using virtual reality technology – and robotics operations, alongside habitat maintenance, personal hygiene, exercise and crop growth.

The 1700 square foot Mars habitat simulation was created with 3D printing.

There are various ways to send astronauts to Mars, but the lowest energy transfer – and most realistic option – is known as a Hohmann...