IDENTICAL twin astronauts, Scott and Mark Kelly, are subjects of NASA’s Twins Study. Scott (right) spent a year in space while Mark (left) stayed on Earth as a control subject. Researchers looked at the effects of space travel on the human body.
According to Nasa (America’s National Aeronautics and Space Administration), Kelly was part of a twins study to figure out how a year in space affected the body.
While 93% of Kelly’s genes went back to normal after a few days back on Earth, the remaining 7% could spell longer-term changes to his immune system, DNA repair, bone formation networks, hypoxia, and hypercapnia.
They didn’t just test his genes – Kelly appears to be no less intelligent relative to his brother after a year in space, though he is physically a bit slower and less accurate, possibly because he had to readjust to Earth’s gravity.
The research on Kelly and his one year mission into space is a stepping stone for a three-year mission to Mars.