When NASA astronaut Scott Kelly came down to Earth after spending a year aboard the International Space Station, he flew back to the planet as a record holder. Kelly clocked 520 days in space over ...

When NASA astronaut Scott Kelly came back down to Earth after spending a year on the International Space Station, the first thing he did was take a deep breath of cold air. "Crisp coldness of the ...

When Scott Kelly (right) goes to the International Space Station in 2015, he and his twin brother Mark (left) will participate in tests to study how spaceflight affects the body. Left image ...