The European Space Agency (ESA) has reported that the crew selection for a simulated Mars mission moved a step closer to completion recently as the last eight candidates are being put through extensive medical screening in Moscow. Two of the European candidates will be chosen to join four Russian crew members on a 105-day study due to start in March next year.

For 105 days, as part of a cooperative project between ESA's Directorate of Human Spaceflight and the Russian Institute for Biomedical Problems (IBMP), the six-strong crew will live, eat, sleep and work in a specially designed and recently refurbished facility in Moscow. There were also consultations with specialists including an ophthalmologist. During this time, they will experience elements of a simulated Mars mission. Their stay is a precursor to the full Mars500 study due to start later in 2009, which will see another six-member crew sealed in the chamber to experience a complete 520-day Mars mission. The purpose of the Mars500 study is to gather data, knowledge and experience to help prepare one day for a real mission to Mars. The participants will act as subjects in scientific investigations to assess the effect that isolation has on various psychological and physiological aspects, such as stress, hormone regulation and immunity, sleep quality, mood and the effectiveness of dietary supplements.