"The biggest change [while living on the space station] is exposure to radiation. He worked with Chris Hadfield, before, during and after his five-month stint on the International Space Station from December 2012 to May 2013. (NASA)While no astronauts who have lived aboard the space station have reported having cancer, it may still be too early to tell. 'You feel helpless'If there's anyone who can tell you about the challenges of living in space, it's Scott Kelly. Kelly was aboard the International Space Station with two months left in his mission at the time.

Source: CBC News November 11, 2017 09:56 UTC