What happens to our body after a long time in space? Results from a study carried out by twins confirm that some changes develop in our body… but not a lot! This could be encouraging news for long duration space voyages in the future. Read on to find out more about their study.
Return to normal after 6 months
The idea involved sending the astronaut, Scotty Kelly into space for a year long mission and then compare his bodily reactions to his twin who remained on Earth, Mark Kelly. In April 2019 the conclusions of the study carried out in 2015 were published in the journal Science. It turns out that Scott Kelly was practically just as healthy both physically and mentally as his twin. What is more any of the major changes observed in Scott returned to normal in only six months.
“I think it is reassuring to know that when you come back you will be in relatively the same condition that were in before you left,” stated Micheal Synder, the director of the Genome and Personalised Medicine Centre in Standford.
As mentioned above some changes were observed all the same. For example some of Scott Kellys genes had changed their expression during his time in space. About 7% of these changes in gene expression could be observed six months after his return to Earth. NASA emphasise however that the epigenic changes were relatively minor especially for a person that is going through a stressful situation like being in space.
However other results also came back. Cognitive tests carried out before and after his mission in space suggested that Scott’s performance in terms of speed and accuracy declined after his return to Earth.
Another interesting remark involves telemeres. These are types of little plugs positioned at the end of our chromosomes which continually shorten with age. Before the mission to space, Scott and Marks telemeres were similar however Scott’s seemed to elongate during his time spent in space at the International Space Centre.
For the time being, researchers have not identified the reason behind this elongation. However they have stated that this discovery “can’t really be seen as a fountain of eternal youth” or as proof that humans could “live longer in space“. The length of Scott’s telemores have “very quickly” decreased after Scott’s return to Earth.
More hope for Mars voyage
These results are encouraging and can help NASA prepare itself for future long duration missions to Mars and beyond. “Given that the majority of biological variables have remained stable or have returned to their baseline, these data suggest that human health can generally be maintained during this length of space flight,” the US agency said in a statement.
This is just the beginning. Living on the International Space Station is not the same as going to Mars as exposure to radiation would be at least five times higher during the trip. The sample is also far too small by only analysing the results of two people. This means that it’s difficult to make definitive conclusions. Further research on other astronauts will be needed to confirm these results with more clarity.