NASA and SpaceX will be launching astronauts from the U.S. for the first time since 2011. The SpaceX Crew Dragon capsule will fly two astronauts, Bob Behnken and Doug Hurley, to the International Space Station. It will be the first crewed launch for Elon Musk's space company SpaceX and the first time ever that NASA has launched astronauts in a commercially-built craft. Leroy Chiao, former NASA astronaut and International Space Station commander, joined Closing Bell to explain how significant a successful mission would be, and how much pressure there is on Elon Musk to be successful on his first attempt.