It’s been a year-long experiment into the effects of space on the human body, but now NASA astronaut Scott Kelly and cosmonaut Mikhail Kornienko have returned safely to Earth.
Acting as human guinea pigs, in the kindest sense, Kelly and Kornienko have spent a year in space in order to see whether the human body can withstand long durations in space, all as part of our attempts to see whether deep space missions with humans is possible.
The pair were returned to their home planet at 10.26am local time (4.26 GMT) in the steppes of Kazakhstan aboard a Soyuz TMA-18M spacecraft.
Joining Kelly and Kornienko was cosmonaut Sergey Volkov, who arrived aboard the International Space Station (ISS) on 4 September last year.
#Thanks for following our #YearInSpace The journey isn't over. Follow me as I rediscover #Earth! See you down below! pic.twitter.com/7byNy6fMG4
— Scott Kelly (@StationCDRKelly) March 1, 2016
The record-breaking pair, however, had launched into space on 23 March last year to embark on what would be called the year-long mission, despite the fact that they spent just a total of 340 days in space.
During that time, the ISS crew conducted more than 400 scientific experiments, but Kelly and Kornienko were assigned a whole range of separate experiments as part of NASA’s Journey to Mars research programme.
While aboard the ISS, the pair were hooked up to monitoring devices capable of reading how the human body adjusts to weightlessness, isolation, radiation and the stress of long-duration spaceflight.
Next stop, Mars
NASA highlighted one of the research projects undertaken by Kelly, which examined fluid shifts that occur when bodily fluids move into the upper body during weightlessness. NASA believes these shifts may be associated with visual changes and a possible increase in intracranial pressure, one of the greatest challenges to overcome before we can send people into space for years-on-end.
During his time aboard the craft, Kelly brought the wonders he was able to see aboard the ISS to those of us here on the ground using social media, which led to the release of some incredible images.
Following this mission, Kelly has now spent a total of 520 days in space, making him the NASA astronaut with the most amount of time spent in space, with his last mission seeing him complete three spacewalks.
It will be a quick turnaround, however, for the remaining crew of the ISS, with NASA astronaut Jeff Williams and Russian cosmonauts Alexey Ovchinin and Oleg Skripochka scheduled to join the ESA’s Tim Peake and others onboard on 18 March.