The Atlantis mission will close the books on NASA's space shuttle program. Where does space exploration go from here?
This morning, CNN's Ali Velshi takes an in-depth look at the future of space travel with Jim Halsell, a former astronaut who has flown five shuttle missions - two as a commander, three as a pilot. He's now a vice president with ATK Aerospace Systems, working on a commercial vehicle to take NASA's astronauts back to space.
In this video, he explains where he thinks space travel will go in the future.