Watch SpaceX's 'most difficult launch ever'
- For the first time, SpaceX has launched its Falcon Heavy rocket with US Air Force payload onboard.
- It's also the first time that SpaceX has launched its Falcon Heavy with reused rockets. Both side boosters landed successfully although the center core missed the landing platform.
- The launch is an audition of sorts to get SpaceX a potentially multibillion-dollar government contract for future launches.