Article Posted on : - Feb 14, 2011

MOSCOW (AFP): A group of volunteers will step out for a "space walk" on Mars Monday, as an unprecedented one-and-a-half year experiment to study the effects of a mission to the Red Planet reaches its climax.

Two volunteers from Italy and Russia will step onto a sandy mock-up of the Martian surface, at around 1:00 pm (1000 GMT) after a grueling eight-month journey -- all without ever leaving a Moscow research centre.

The space walk comes around halfway through the experiment in which the participants spend 520 days in isolation to test how humans would respond to the pressures of the long voyage to Mars.

The men's first steps will be relayed to the Russian control centre that monitors real space missions, as part of an experiment organised by the European Space Agency and Moscow's institute of biomedical problems.

A team of six men from Europe, Russia and China has been locked since June in a mock-up spaceship at the institute to test the psychological effects of an 18-month round trip in the experiment, called Mars-500.

The volunteers aged from mid-20s to late 30s, among them engineers, doctors and a physicist, are crammed into the spaceship, where living quarters measure just 20 metres (yards) long and less than four metres across.

Russian Alexander Smoleyevsky and Italian Diego Urbina will be the first to step out, after transferring Saturday to a smaller landing module and "touching down" on Mars, along with Chinese volunteer Wang Yue.

Three other volunteers, Romain Charles from France and Sukhrob Kamolov and Alexei Sitev from Russia, will remain "in orbit" in the main module.