SPACE TRAVEL CAN ALTER GENES, SAYS NASA

Astronaut Scott Kelly spent a year in space while his identical twin, Mark, stayed on Earth, giving scientists the perfect subjects to study the effects of space travel on humans. According to preliminary studies, Scott’s genes — including the size of the chromosomes, motor skills and muscle dexterity, and gut microbiome — have undergone changes, compared to Mark. This data could determine the success of the various plans to send humans to Mars over the next couple of decades.