The final preparations are underway to put a Russian and American astronaut into space for a full year - an important step as each country's respective space agencies prepare to move humanity's explorers into deeper space.

Experts with NASA, the European Space Agency (ESA), and Roscosmos have long struggled to better grasp the effects spending time in space can have on a human being. Dogs, rats, and geckoes have all spent significant time in space to better understand physical factors; while humans have spent months and months in remote sites to reveal psychological changes. Nothing, however, beats the real McCoy - that is, studying humans in space.

That's why researchers are very thankful for NASA astronaut Scott Kelly and Russian Federal Space Agency (Roscosmos) cosmonaut Mikhail Kornienko, both of whom will be spending a year living and working aboard the International Space Station (ISS). They will begin their mission, along with cosmonaut Gennady Padalka, as part of the ISS Expedition 43 crew.

The trio will head up to the ISS in a Soyuz spacecraft this Friday (March 27), launching from the Baikonur Cosmodrome in Kazakhstan around 3:40 pm EDT. NASA TV coverage of the launch will start around 2:30 pm, and as long as all goes well, the astronaut and cosmonauts should be stepping foot inside the ISS by 10:45 pm that same night. (Scroll to read on...)

And while Kelly and Kornienko are not the first men to spend more than 365 days in space, they are the first humans since 1994 to specifically be using this time to learn more about the environment's effects on things like bone density, immune systems, internal adaptations to microgravity, and even mental state.

"Data from the expedition will be used to determine whether there are ways to further reduce the risks on future long-duration missions to an asteroid and eventually Mars," NASA added in a recent release.

Prior to this experiment, Valeri Polyankov and Sergei Avdeyev, Russian cosmonauts from the mid-1990s, spent the longest time in space, clocking in just under 438 and 380 days, respectively.

Polynakov, who spent his time aboard Roscosmos' Mir orbital station (now retired), said on the advent of his landing that "it is possible to preserve your physical and psychological health throughout a mission similar in length to a flight to Mars and back."

Now, with huge advances in space-science and medical fields, we will find out if he was right.

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