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Elon Musk's SpaceX has successfully performed another launch of its Starship rocket in front of President-elect Donald Trump, but the test flight did not go perfectly.
The 400ft (122m) high rocket system, designed to land astronauts on the moon and ferry crews to Mars, lifted off from Boca Chica, Texas.
The first stage, called Super Heavy, unexpectedly made a splashdown in the Gulf of Mexico instead of attempting to return to its launchpad, indicating something went wrong.
Mr Trump's appearance signals a deepening alliance with Mr Musk, who stands to benefit from his recent election victory.
The billionaire entrepreneur is expected to secure favourable government treatment, not only for SpaceX but also Tesla, and help his companies.
Mr Trump has also appointed Mr Musk as co-leader of a new government efficiency project.
After separating from the Starship second stage, the booster returned to Boca Chica in Texas, where it was supposed to be grabbed and clamped in place using what the company describes as "chopsticks".
Arguably, they look more like massive pincers mounted on a huge steel tower.
Booster catch was a 'no-go'
But the booster catch was called off just four minutes into the test flight and the booster hit the water three minutes later.
"We are a no-go for tower catch," said SpaceX, adding the 'criteria' was not met, although the firm did not specify what went wrong.
The Starship rocket also splashed down around an hour later, but this time in the Indian Ocean, off the northern coast of Australia.
It descended in a "belly flop" position before its central engines flipped it around.
Analysis: This is not the outcome any party wanted to see
Science and technology editor
Elon Musk will be very disappointed by the failure to catch the booster with Donald Trump watching on.
This was their moment to show their prowess in efficiency, reusability, the "fail-fast efficiency" that Donald Trump really wants his presidency to embody.
Donald Trump isn't somebody who wants to be associated with things that don't look brilliant or work amazingly.
Instead, Trump wanted to be associated with Musk's glory and that hasn't happened.
This was a flight test with a political moment tagged on to it and I think it will have been not the outcome that any party wanted to see.
Step towards moon trip
It was the sixth test for the world's biggest and most powerful rocket that SpaceX and NASA hope to use to get astronauts back on the moon and eventually Mars.
Among the objectives for the test were igniting one of the engines in space and thermal protection experiments aboard the spacecraft.
SpaceX wants to eventually return and reuse the entire Starship, as full-scale recycling would drive down the cost of hauling cargo and people into space.
NASA is paying SpaceX more than $4bn (£3.1bn) to land astronauts on the moon via Starship on back-to-back missions later this decade.