"It is kind of like having roommates that just are always there and you can never escape them”Martian Hawaii: Mauna Loa from Mauna Kea panoramaLaoise Fitzpatrick takes a look what life on another planet (in this case, a simulation on Hawaii) would really be like.A team of six has recently concluded an experiment into one of the most volatile aspects of a potential manned space mission to Mars: the human factor. How well can a small team cope when having to live and work in a tiny space together to and from the Red Planet? This is the question that the HI-SEAS IV (Hawaii Space Exploration Analogue and Simulation 4) experiment hoped to answer.The mission brief was to determine how to keep a crew healthy and happy while on a long-term mission such as one to Mars. The research would cover food, interpersonal dynamics and behaviours, and work performance over the course of one year. This is the fourth such experiment, with the prior three lasting 4 months, 120 days, and 8 months respectively.To simulate the type of structures that could be constructed for a Mars mission, the crew spent the year inside a two-storey dome, which was fitted with cameras and movement trackers to analyse their behaviour. The ground floor of the dome contained a kitchen, dining area, office, laboratory and a bathroom with shower. The second floor contained the crew’s bedrooms which each consisted of just a bed, desk and chair. The crew was forced to spend almost all of their time in this small area with little to no privacy or personal space. They were allowed short excursions outside the dome in a space suit to simulate experiments that would be required during a real mission.Resources were strictly controlled to imitate the realities of long term missions. Water was rationed and food was limited to freeze-dried, long-lasting food which had to be rehydrated to be eaten. As well as this, the air was recycled as there would be no oxygen atmosphere to rely on during a Mars mission.The crew consisted of a French astrobiologist, a German physicist, and four Americans: an architect, a soil scientist, a pilot, and a journalist. Upon leaving the dome at the end of August the crew was optimistic about the potential for real Mars missions to succeed, with French crew member Cyprien Verseux stating "I can give you my personal impression which is that a mission to Mars in the close future is realistic. I think the technological and psychological obstacles can be overcome." Other crew members however noted the difficulty of living in such close proximity to others for so long. Carmel Johnston, the mission commander, stated "it is kind of like having roommates that just are always there and you can never escape them so I'm sure some people can imagine what that is like and if you can't then just imagine never being able to get away from anybody."This experiment is the longest of its kind since a Russian experiment which lasted 520 days. The Mars mission will not to be the last; at least two more will take place, with the next to begin in January 2017.