Though many astronauts have spent more than 365 days in Space, it has not been in one long stretch, but instead broken up through several missions. That is because scientists are not sure of the long-term effects of weightlessness on both the human body and mind, and therefore restrict stays to a maximum of six months.

However, if we are ever to make a trip to Mars or even an asteroid, then researchers need to ensure that the astronauts can withstand each other for such long periods of time in really tiny quarters and more importantly, if their bodies and minds can handle the harsh long journeys.

The first issue was tested out in June 2010. Called Mars 500, the mock mission entailed sequestering six astronauts in a sealed 1,000sq.ft. capsule for a full 520 days. During that time, they did everything the astronauts going to the Red Planet will be required to do, except for one thing . . . . . . Leaving earth!

Now researchers are planning the next phase of the tests by actually sending two astronauts to Space for an unprecedented amount of time - This time to study the negative effects, if any, that micro-gravity may have on the human body and mind. Since the only place we are currently situated in Space happens to be the International Space Station (ISS) that, is where they will be spending an entire year!

The two scientists selected for this rather risky experiment, US astronaut Scott Kelly and Russian Cosmonaut Mikhail Kornienko, are both experienced space explorers who have been to the ISS on multiple missions.

48-Year old retired US Navy captain Scott Kelly, has spent a total of six months at the Station made his first trip in mission STS-103 in 1999. He subsequently made two more trips, one as a commander of the space shuttle flight. His companion to be, 52-year old Kornienko first visited the ISS in 2010 and has to date logged a total of 176 days at the Station.

However, before the duo begin their ground-breaking endeavor in March 2015, they will spend two years training for it, on earth. Once at the ISS, their health, mental well-being and performance will be closely monitored for the entire year. The results will help the scientists ascertain the best way to keep the pioneering astronauts that will make the trip to outer space, healthy and happy!

Surprisingly though, while the year in space will place Kelly and Kornienko ahead of most other space explorers they will not be able to edge out the record set by Russian cosmonaut Valeri Polyakov, who left aboard the Soyuz rocket in January 1994 and spent a total of 438 days at the Russian Space Station Mir. During the time he performed scientific research, conducted several experiments and orbited the earth 7,000 times!

His reason for spending so much time in one continuous stretch? The same as the one the two astronauts are being sent for! Turns out, he did quite well, even managing to walk the few steps between him and and his capsule that brought him back to earth on March 22nd 1975, following his extended stay in weightless conditions. The best part is that scientists found no long lasting impairment and Mr. Polyakov is still around at the ripe old age of 70! Hopefully, Scott Kelly and Mikhail Kornienko's extended stay at ISS will have a similar outcome.

Guardian.co.uk, wikipedia.org