In the name of science, former NASA astronaut Scott Kelly shoved himself into the top of a rocket, accelerated to 17,500 mph, and fell around Earth for 340 days — nearly an entire year.
The lack of gravity, radiation exposure, Kelly's diet, and other facts of life in orbit affected his body in significant ways — including, as NASA is learning now, even perhaps his genetic blueprint.
The Twin Study, which is still in progress, uses Scott Kelly's identical twin brother and fellow former astronaut, Mark Kelly, to unmask the subtle but important effects of long-duration space travel on the human body.
Here are eight biological oddities that researchers have found happen to your body if you're in space for a year.
Your face looks different.
Your bone density can change.
Your body fluids shift.
Your sight could change.
Your muscles can atrophy.
You'll be sleepy.
Your cancer risk increases.
You get taller — until you get back to Earth.
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