Magazine science publishes an important study for the future of manned flights. Because one of the biggest difficulties in sending astronauts to Mars is how their bodies will be able to withstand years of return travel.
NASA has already conducted studies on astronauts. But how do you make sure that biological changes are linked to weightlessness, and not just to aging of the body?
It turns out that the government agency counted among its ranks Twins, Kelly. Mark Kelly he was a shuttle pilot until 2011. His twin brother, Scotthe was also chosen for several missions, including 340 consecutive days on the International Space Station in 2015-2016.
A team of 84 scientists then implemented it a program to study in detail the body of Scott Kelly in spaceand that of his brother Mark on Earth.
A battery of tests carried out for 27 months
For 27 months, before, during and after the mission, the two brothers had to submit very thorough test seriesand collect their blood, their plasma, their urine, their feces. That seems simple in appearance, but bring back to earth regularly all these liquids, transported for each trip rocket. One of them exploded, which has almost challenged the whole experience.
The genetic evolution of magnitude seems to be related to space
The body of the twin in weightlessness has changed, his bones are refined because they no longer had to carry the weight of the body, the atrophied muscles. What was expected. But what has impressed scientists most is the extent of genetic evolution. Which we know directly relating to space theftbecause his brother on Earth originally had exactly the same genetic makeup.
In total a thousand genes have changed. Which is not a genetic mutation, but the DNA has been discontinued. As if his body had been attacked. A phenomenon that has consequences on the immune system, which was on alert.
The resistance of the human body to the test of the journey
And this genetic modification accelerated as the mission progressed. These changes gradually faded when Scott returned to Earth. finally, 90% of its genes are back to normal. We will have to wait years to know if this will have long-term consequences, good or bad, nobody knows.
For example, will he grow older faster than his brother or, on the contrary, later? But this study suggests this the human body seems robust enough endure a long journey, perhaps on Mars.