VANDENBERG AIR FORCE BASE, California, Jan 17 Reuters - A SpaceX Falcon 9 rocket has blasted off from California and successfully put a climate-monitoring satellite into orbit, but botched an attempted return landing on a platform at sea, officials say.
The first stage of the rocket made it back to the platform, which was floating in the Pacific Ocean, but it apparently landed too hard and broke one of its landing legs, technology entrepreneur Elon Musk's SpaceX wrote on Twitter.
On Sunday, the 22-storey-tall rocket lifted off through thick fog from Vandenberg Air Force Base on the central California coast at 10.42am PST (0542 AEDT Monday), a NASA TV broadcast showed.
A successful ocean landing would have marked a second milestone for SpaceX a month after it nailed a spaceflight first with a successful ground landing in Florida, a key step in Musk's quest to develop a cheap, reusable rocket.
The company's two previous ocean-landing attempts in 2015 were also unsuccessful. Being able to land at sea would give the company flexibility to recover rockets used on more demanding missions, such as launching heavy satellites, when boosters do not have enough fuel left to reach land.
However, the SpaceX launch succeeded in sending the US- and European-owned Jason-3 satellite into orbit.
The 550-kilogram Jason-3 satellite is the fourth in a series of ocean-monitoring satellites, which are taking centre stage in monitoring Earth's climate.
"More than 90 per cent of all the heat being trapped in the Earth's system ... is actually going into the ocean," said Laury Miller, Jason-3 lead scientist with the National Oceanic and Atmospheric Administration.
"This makes the ocean perhaps the biggest player in the climate change story."
NOAA is one of five agencies partnering on the $US180 million ($A263 million), five-year Jason-3 program.
Once in position 1336 kilometres above Earth, Jason-3 will bounce radio waves off the ocean and time how long it takes the reflected signals to return.
Scientists can use the information to figure out ocean heights to within 0.5cm, said Josh Willis, of NASA's Jet Propulsion Laboratory in Pasadena, California.
Jason-3 can also chart ocean currents, which impact weather phenomena such as this year's powerful El Nino system, monitor tsunamis and track oil spills.
