Inside the 3D-printed box in Texas where humans will prepare for Mars

Starting this June, four volunteers will spend a year pretending to live on the red planet inside the Mars Dune Alpha habitat

Red sand shifts under the boots of the crew members. In the distance, it appears that a rocky mountain range is rising out of the Martian horizon. A thin layer of red dust coats the solar panels and equipment necessary for the year-long mission.

This landscape isn't actually 145m miles away. We are in a corner of the Nasa Johnson Space Center in Houston, in a large white warehouse right next to the disc golf course and on the tram route for tourists and school groups.