Chris Cassidy is a retired NASA astronaut and United States Navy SEAL. Chris Cassidy achieved the rank of captain in the U.S. Navy. His first spaceflight was on a Space Shuttle mission in 2009. He ...

In half a lifetime, Jonny Kim has achieved the American dream three times over. He was a Navy SEAL. Then he graduated from Harvard Medical School. And on Tuesday, he blasts off as part of his latest ...