Simulated Mars mission 'returns' to Earth

Katharine Sanderson

Early afternoon in Moscow today, 4 November, the hatch of a hermetically-sealed capsule opened for the first time in 520 days. From the box emerged six pale, possibly immune-impaired but otherwise fit men who had just completed the longest-ever study of human isolation: a simulated mission to Mars and back.

The six crewmen — three Russian, one Chinese, one French and one Italian — have spent the past year and a half living in three small rooms in the Institute of Biomedical Problems in Moscow, enduring a living space of just 550 cubic metres. They have been subjected to hundreds of physical and psychological tests, provided thousands of samples of urine and blood, and endured communications delays of up to 20 minutes since entering their 'spaceship' on 3 June 2010, as part of the Mars500 experiment.

Their efforts have allowed scientists to gather crucial data on how humans cope with claustrophobia, boredom and being cooped up with the same people in a small space for an extended time. "We have learned that you can put six guys in isolation for a year and a half and they can perform well," says Christer Fuglesang, the European Space Agency's head of the Science and Applications Division in the Directorate of Human SpaceFlight and Operations, who oversaw the project.

Far from real

 But the exercise is a long way from simulating the pressures of a real mission to Mars, some observers point out. Even though they were isolated and subjected to simulated emergency situations, such as power cuts, the crew members were not presented with any real risk. "The fact that any one of them could bang on the door and ask to be let out does detract from the simulation," says Jason Kring, a psychologist in the Human Factors and Systems Department at Embry-Riddle Aeronautical University in Daytona Beach, Florida.

Perhaps a better place to run such an experiment would be in a remote place such as Antarctica, says Sheryl Bishop, a biostatistician and psychologist at the University of Texas Medical Branch in Galveston. "I rue the lost opportunity," she says. "They could have done this exact experiment in an environment that was truly remote and in the winter months was truly dangerous."

"We couldn't mimic the danger factor," admits Fuglesang. Moscow was chosen because of the need to have all the control staff present, he says. "What made it harder [for the crew] is they're just staying in there. They're not going to Mars for real," Fuglesang adds. It was impossible to create the pressure and motivation that a real journey to Mars would engender, even though the crew did simulate a walk on the surface of Mars halfway through their isolation.

The simulated time-delay in communications was one realistic aspect of the mission, says Kring. In previous human space flights, mission control has always been consulted for every technical task, even telling the astronauts when to wake up and when to go to the bathroom. But with a 20-minute delay, a real Mars crew would have much more autonomy, says Kring. If a fire starts, for example, it would be 40 minutes before mission control could respond. Experiences of the time delay in Mars500 will help to shape the necessary changes in operational procedures for real Mars missions.

Kring has other concerns. "I'm disappointed that there were no women," he says. "I think the first mission to Mars will have a woman on board." Kring and others have looked closely at the effect of mixed-gender crews, and he thinks that having both men and women is crucial. A team is more civilized with women and men present together, he says.
nature.com