What is the damage to the body of astronauts going to space? NASA astronaut Scott Kelly spent 340 days on the international space station. Scientists were very curious about whether his physical condition had changed. So they found his twin brother Mark Kelly, who had the same gene as him, and compared him. The results showed that Scott's' immune system and DNA repair function 'had a mutation. From the genetic point of view, it was a permanent damage that could not be recovered.
According to a research report in the journal Science, three years after Scott, 55, returned to earth, scientists carried out a whole-body examination on him and found that during his stay in space, his carotid artery and retina became thicker, his weight became lighter, his intestinal microbes increased, and his cognitive ability decreased. However, most of these symptoms gradually disappeared six months after he returned to earth, only 8.7% of his genes changed to normal It has not yet recovered.
Scott said that the days when he just returned to the earth were very hard. For a long time, he had no energy and was very tired. "I thought I had the flu.".
Rachael Seidler, a cognitive neuroscientist at the University of Florida, said: 'these mutations do not pose a direct risk to astronauts, but do not rule out increasing their risk of cancer in the future. '
Susan, a cancer biologist at Colorado State University Bailey) said that there is a part called telomere at the end of human chromosome, which will shorten gradually with age. Radiation, pollution, pressure and other factors may cause it to shorten rapidly. However, it is strange that after Scott went to space, the telomere did not shorten, on the contrary, it was longer than before. In other words, "his cells are younger than before." it is very likely that It's' space wakes up some sleeping cells in his body '.
Researchers pointed out that there are five possible mutations in Scott's gene, including the impact of space radiation and zero gravity environment on physiology, because the space station where Scott was originally staying was just in Van Allen, a high-energy charged particle Under the radiation belt, the amount of radiation is 48 times that of the earth, so the cells of the body will be busy repairing the radiation damage.