Six scientists have just embarked on the journey of a lifetime, even though they aren’t really going anywhere. They have entered a man-made dome on a remote volcano on Hawaii as part of a human-behavior study to help NASA figure out how to send astronauts on the long journey to Mars.

The four men and two women moved into their new home on Thursday atop Mauna Loa, with just 1,200 square feet of space to share. They won’t be able to talk to anyone in the outside world and must operate on a 20-minute delay with the support crew, which simulates how long it would take for communications to reach Earth from Mars.

The purpose of the project is to study the psychological difficulties of living in such an isolated and enclosed place for a long period of time, which will help them make preparations when they have to really send astronauts to Mars.

The University of Hawaii said in a statement about the domed site: “The HI-SEAS site has Mars-like geology which allows crews to perform high-fidelity geological field work and add to the realism of the mission simulation. The Martian regolith examined by the CheMin instrument (Blake et al. 2012) is very similar to the weathered basaltic materials found in this part of Hawaii. The site is a former cinder rock quarry on the side of a spatter cone. It is surrounded by relatively recent lava flows with very little plant or animal life present. None of the sparse flora or fauna is rare which mitigates the likelihood of adverse environmental impact due to mission activities. The flows include a wide variety of volcanic features to explore, such as lava tubes, skylights, channels, and tumuli. The HI-SEAS site is visually isolated, yet accessible by a dirt road, and a hospital and other emergency services are within a one hour driving distance (much less by helicopter). It has a cool, dry climate that varies very little over the year, enabling long-duration missions.”