NASA to Launch Longest Space Mission

American astronaut Scott Kelly will begin NASA’s longest-ever space trip Friday, when he and two Russian colleagues will take off for a year-long mission at the International Space Station. The longest previous NASA trips have only lasted as long as about six months, but the full year will push three-time space veteran Kelly’s total days in orbit to more than 500. As a bonus, scientists will compare Kelly’s health while in space to that of his twin brother, Mark, to examine the effect of long-term space travel on the human body. Takeoff is scheduled for the mid-afternoon from Kazakhstan.