A SpaceX Falcon 9 rocket blasted off from Florida on Friday and delivered a communications satellite into orbit, but failed to land the launch vehicle intact on to a landing platform floating in the Atlantic about 400 miles (645 km) off Florida's coast.
The rocket, carrying the 12,613-pound (5,721 kg) Boeing-built satellite, lifted off from Cape Canaveral Air Force Station at 6:35 pm EST/2335 GMT. The launch, which had been delayed four times since Feb. 24, marked the second of more than 12 SpaceX flights expected this year.
The satellite is owned by Luxembourg-based communications network operator SES SA.
However, the Falcon's upper stage managed to place the satellite into its intended orbit more than 25,000 miles (40,600 km) above Earth.
In December, a returning Falcon 9 rocket successfully touched down on a ground-based landing pad in Florida, an unprecedented milestone in Musk's quest to develop a cheap, reusable booster.
The rocket flying on Friday was traveling too fast to return to land, prompting SpaceX to try the ocean landing.
"Given this mission's unique ... profile, a successful landing is not expected," SpaceX said in a statement before the launch.