MARS SIMULATION PROJECT 
- Aim is to gather knowledge and experience to help prepare for real Mars mission
-  This means probing the psychological and physiological effects of extended isolation
-  Project simulates outward cruise, landing operations and return journey to Earth
-  Over 100 experiments planned; crew partake in a series of medical studies
-  Resources restricted at departure; crew has to manage food consumption
-  Text communications only are possible with the ground; 20min delay in signal
The crewmembers will soon step out on a simulated Martian surface.
The crew of the Mars500 simulated mission to the Red Planet have reached a key milestone.
The six men, sealed since June inside steel containers representing a spacecraft, have "gone into orbit" at their destination.
Three of the group will now "descend" to the planet, don real spacesuits and walk on the "surface" of Mars.
In reality, this surface will just be the sandy floor of another module at the Moscow-based experiment.
The Mars500 project is run by Russia's Institute of  Biomedical Problems with the participation of the European Space Agency  (Esa).
It aims to investigate some of the psychological and  physiological effects that humans might encounter on a long-duration  spaceflight.
"So far, I must say we've had no major problems," said Martin  Zell, who heads up the Esa scientific programme on the International  Space Station (ISS).
"There is permanent monitoring, so we understand their health  very well. We have a lot of data now on their mental state and on how  their bodies are reacting.  That's important because there is a link  between the two," he told BBC News.
The crew comprise three Russians, two EU citizens and a Chinese national.
Alexander Smoleevskiy, Sukhrob Kamolov, Alexey Sitev, Diego  Urbina, Romain Charles and Wang Yue all had to pass through a rigorous  selection procedure to get on the programme, and their "departure" on  the grounded spaceship last year drew wide international attention and  curiosity.
For eight months, the group has  worked together inside the closed facility which has no windows and a  total interior volume of about 550 cubic metres (19,423 cubic feet). 
The coming days will see Smoleevskiy, Urbina, and Wang enter a  "descent module", from where they will have access to a further  container that has been set up to look like the dusty terrain of Mars.
The trio will put on the type of spacesuit worn by real  cosmonauts and simulate the sort of geological investigations future  astronauts might pursue on the Red Planet one day.  Three sorties are  planned, with the first outing due to take place on 14 February.
A robot rover will assist the Mars walkers, and their  activity will be overseen by Mission Control Moscow which normally deals  with events on the ISS.
"They will go on to the surface two at a time, with one man staying behind in the landing module," explained Dr Zell.
"Working in their suits, they will have a drill to get below  the surface; and they will do a virtual analysis of the samples the  drill delivers to them.  They will also take samples back to the module  for further analysis."
Although the Mars500 experiment has not been able to simulate  the constant weightlessness of a genuine eight-month journey through  space, it has been able to introduce one important realism - that of a  time delay in the communications between the crew and their ground  controllers outside the modules.
Messages take 20 minutes to pass between the two ends of the  link, similar to the lag radio messages travelling the great distance  between Mars and Earth would come up against.
This proved particularly testing last month when controllers  deliberately - and without warning to the crew - cut the power to the  modules.  They even blew a small amount of smoke into the containers to  give the men inside the sensation that they were dealing with a serious  electrical failure.
"They spent almost a day without energy," Dr Zell said.   "They had to work through their emergency procedures and analyse the  situation.  They didn't panic and they remembered their training."
Mars500 is so called because it simulates the duration of a  possible human Mars mission in the future using conventional propulsion:  250 days for the trip to the Red Planet, 30 days on the Martian surface  and 240 days for the return journey, totalling 520 days. (In reality,  it would probably take a lot longer than this.)
The six men are due "back on Earth" in November.
THE LAYOUT OF THE MARS500 'SPACESHIP' 
-  MEDICAL MODULE: A 12m-long cylinder that acts as the  laboratory. Should a crewmember become ill, he can be isolated and  treated here 
-  HABITABLE MODULE: The main living quarters. The 20m-long module  has beds, a galley, a social area. It also acts as the main control  room 
-  LANDING MODULE: This will only be used during the 30-day landing operation. Three crewmembers will visit the "surface"
-  UTILITY MODULE: It is divided into four compartments, to store  food and other supplies, to house a greenhouse, a gym a refrigeration  unit
-  SURFACE MODULE:  To walk across the soil and rocks of Mars,  crewmembers must put on Orlan spacesuits and pass through an airlock
Source: bbc.co.uk/news/science-environment-12337108