Romain Charles and Diego Urbina have been chosen to go into a set of steel containers on 3 June with two Russians and a Chinese national.
The group’s exile will test the physical and mental requirements of ultra-long duration spaceflight.
Their Mars500 “spaceship”, which is located in Russia’s Institute of Biomedical Problems, has no windows.
All the food and water needed for their “journey” will have to be loaded before “departure”.
The experiment’s designers intend to make the exercise as realistic as possible by introducing a time delay in communications after two months.
Because it can take about 20 minutes for a message to travel from Mars to Earth, it will take this amount of time in the simulation, also.