Russia's Roscosmos space agency has suggested expanding the length of future expeditions to the International Space Station from the current six months to a year and even longer to provide for the next step in space exploration - manned spaceflights beyond low-Earth orbit.

Earlier, the countries involved in the ISS project agreed that the station could remain operational until 2020. Rocosmos believes that the remaining time should be used to simulate long-duration interplanetary flights in orbit along with similar experiments on Earth, the latest of which, Mars-500, ended last November.

A crew of six volunteers spent 520 days in complete isolation in an experimental facility at the Institute of Medical and Biological Problems in Moscow, simulating a full-length return trip to Mars.

The same experiment would be far more valuable if performed aboard the ISS. Here's what Roscosmos' manned flight programs director Alexei Krasnov has to say on the subject:

"We and our colleagues are discussing the possibility of repeating the experiment in real spaceflight conditions aboard the ISS. The length of the experiment remains open with various options being considered. Perhaps, there is no need to isolate part of the crew for more than 500 days like we did on Earth. The main aim is to model the self-sustainability of onboard systems, above all life-support systems."

It's impossible to create such factors as for example galactic radiation or zero gravity on Earth. In this regard, the ISS would be an ideal venue for interplanetary flight simulation. Alexei Krasnov:

"The use of the ISS not just for traditional research tasks but also to gain experience and knowledge needed for flights to the Moon and then on to Mars would be most desirable."

Here, a lot will depend on the partners. For example, the Americans did not take part in the Mars-500 experiment, but will they want to join it aboard the ISS? Certainly, this will require more financing. Meanwhile, budget constraints have forced NASA to pull out of the European-led "ExoMars" robotic mission.

It is also unclear how many astronauts should operate the ISS during the experiment, considering that the station can only accommodate a crew of six.

A year-long stay in orbit is quite realistic. Video footage of the first ISS crew upon landing shows that the astronauts were unable to walk due to muscle atrophy caused by a prolonged exposure to zero gravity.

But Russian cosmonauts Vladimir Titov and Musa Manarov stayed in orbit for a whole year, and another Russian cosmonaut, Valery Polyakov, holds the world record for the longest ever spaceflight which lasted 438 days. As for muscle atrophy, it can be successfully fought by physical exercises.

Source: RIA Novosti