The Dallas Morning News
Study finds no bar to longer space stays
Scott Kelly’s body reacted oddly, but he largely bounced back
WASHINGTON — From his eyes to his immune system, astronaut Scott Kelly’s body sometimes reacted strangely to nearly a year in orbit, at least compared with his Earthbound identical twin — but newly published research shows nothing that would cancel even longer space treks, like to Mars.
Kelly largely bounced back after returning home, say scientists in NASA’S “twins study,” whose final results were published in Friday’s edition of the journal Science.
It marks “the dawn of human genomics in space,” said Dr. Andrew Feinberg of Johns Hopkins University. He led one of 10 teams of researchers that scrutinized the twins’ health down to the molecular level before, during and after Kelly’s 340day stay at the International Space Station.
Also, the study points out potential risks of longerduration spaceflight that need study in more astronauts, said Markus Lobrich of Germany’s Darmstadt University and Penny Jeggo of the University of Sussex, who weren’t involved in the work.
NASA already knew some of the toll of space travel, such as bone loss that requires exercise to counter. This time, scientists looked for a gamut of physiologic and genomic changes that Scott Kelly experienced in space, comparing them with his DNA double on Earth, exastronaut Mark Kelly.
Possibly the weirdest finding had to do with telomeres, the protective ends of chromosomes. Those tips gradually shorten as we get older and are thought to be linked to agerelated diseases including some cancers.
But in space, Scott Kelly’s telomeres got longer. Colorado State University’s Susan Bailey, a telomere expert, said she couldn’t explain it, though it doesn’t mean Kelly got younger. Back on Earth, his telomeres mostly returned to preflight average.
Also, the activity of many of Kelly’s genes — how they switch on and off — changed, especially in the last half of the voyage, which ended in March 2016. Again, most gene expression returned to normal back home.