We Finally Learned What a Year in Space Did to Astronaut Scott Kelly ’s Body

Traveling in space looks like all kinds of fun, and in a lot of respects, it is—provided you can overlook a few downsides. There’s the loss of muscle mass, for one thing. Then there’s the decalcification of bones and the stress on the heart and the damage to the eyes and the changes in the immune system and the disruption of the genome and an actual shortening of your overall life expectancy. It was, in part, to study all of those biological problems that astronaut Scott Kelly spent 340 days in space from 2015 to 2016 (chronicled in TIME’s Emmy-nominated series A Year in Space). Now, just over three years after his return, the first tranche of studies into Kelly’s off-world marathon has been published in Science. The results are mixed — Kelly fared better than expected on some measures and worse on others. The overall conclusion is less ambiguous: space travel is exceedingly hard on the human body, and we have a lot to learn before we’re ready to start living on the moon or Mars. One of the things that made Kelly an improbably perfect specimen for the year-in-space study was that he has an identical twin brother, Mark Kelly. Both were NASA astronauts, both are generally fit and healthy and both, of course, share the same basic genome. Take two people with identical genetic software and put them in decidedly non-identical surroundings, and then compare them throughout the year and after. At least some of the differences in health will...
Source: TIME: Health - Category: Consumer Health News Authors: Tags: Uncategorized onetime space Year in Space Source Type: news