MOSCOW, March 31 (RIA Novosti) - A 105-day experiment to simulate a flight to Mars started on Tuesday at the Institute of Medical and Biological Studies in Moscow.

Four Russians - cosmonauts Oleg Artemyev and Sergei Ryazansky, oncologist Alexei Baranov, and sports physiologist Alexei Shpakov - along with two members of the European Space Agency, French civilian pilot Cyrille Fournier and German mechanical engineer Oliver Knickel, are taking part in the experiment.

Each participant will be paid 15,500 euros ($20,000).

Institute Director Igor Ushakov earlier said the 105-day trial is a continuation of the 14-day experiment of November 2007, and precedes the main event, a 520-day simulation flight due to start in late 2009.

The 520-day experiment will simulate all aspects of a journey to the Red Planet, with a 250-day outward trip, a 30-day stay on its surface, and a 240-day return flight.

During nearly two years of isolation, crew members will experience many of the conditions likely to be encountered by astronauts on a real space flight.

They will stick to a rigid daily regime of work, rest and exercise, and follow the same diet as crews aboard the International Space Station.