Watch SpaceX's second attempt at launching a US spy satellite

Yesterday morning, SpaceX had big plans for launching US spy satellite NROL-76 on the back of a Falcon 9 rocket at Cape Canaveral. Unfortunately, a sensor issue put paid to the idea, but just one day later, the company is back and attempting a do-over for the mission. At 7:15am ET, SpaceX will attempt to fire the secretive craft into the heavens and then, crucially, return the Falcon 9 to the ground.

Following separation, the Falcon 9's first stage is hopefully going to return and land on SpaceX's pad at Cape Canaveral. As we pointed out yesterday, the land-based return is fairly unique and means that we'll get high-quality video of the event that isn't normally possible with drone ship landings. It's also another milestone on the road to Elon Musk being able to boast of saving a small fortune on space travel with his reusable rockets.

Update: Success! The first stage has successfully landed back in Cape Canaveral.