Falcon Heavy, world's most powerful rocket, launches – as it happened

Two former astronauts (one a sitting senator) and Nasa’s acting administrator tweet their congratulations to SpaceX.

Senator Bill Nelson spoke with reporters shortly after the launch, too, saying, “we’re going to Mars!”

There is a car with a dummy in it circling the Earth. This is real.

You can watch the car on its journey on the live stream below.

SpaceX has started a live stream of its “starman” – the dummy in the Tesla Roadster cruising toward Mars.

If you rewind to about the five-minute mark, you can catch a spectacular view of Earth. Musk tweets the highlight clip.

Elon Musk has tweeted out an update on the upper stage – his Tesla Roadster is cruising through high-energy radiation belts circling the Earth, toward deep space.

The projected path of the car would bring it close to Mars, but Musk has said there is only an “extremely tiny” chance that it might crash into the planet. If it stays on course, it would instead drift through space, potentially for millions of years.

Reporting from Cape Canaveral, Richard Luscombe has spoken with fellow spectators – most in some stage of frazzled awe at the launch they just witnessed.

Sean Clark and his six-year-old daughter Maia watched the Falcon Heavy power into Florida’s clear blue skies, listened to the double sonic boom as the rocket’s boosters returned to Earth, and declared themselves stunned.

“It’s just wow,” said Mr Clark, who got Maia up before dawn to drive across Florida from Newport Richey to watch the launch at the space centre.

“It’s a whole new generation of kids getting excited about space. This is her third launch, she’s into space and science and I wanted to keep that interest going for the future. I came here for her future. It’s just amazing what Elon Musk has done and is doing.”

Cindy and Patrick Salkeld came from California to watch their first rocket launch.

“It was was overwhelming, better than expected, unbelievable. We couldn’t just see it, we could hear it and feel it vibrating the ground. It was emotional,” said Mrs Salkeld.

Elon Musk, her husband said, was “brilliant”.

“It’s incredible that not only did he get that rocket up there, but then he lands those two pieces right back on the ground upright, right on the circle. How on earth do you do that, it was spectacular.”

Nearby were other reporters, including Miriam Kramer for Mashable. She filmed the launch, capturing the liftoff’s roar. It’s palpable.

There’s still a mystery about the core rocket booster: it was supposed to land on SpaceX’s drone ship in the Atlantic, but smoke obscured the camera and then the feed cut out from vibrations on the deck.

Space Twitter is concerned. Some photos to tide us over.

It’s difficult to overstate what SpaceX has just accomplished: it’s successfully introduced a new heavy rocket to the world, the most powerful in operation and second only to the Apollo era, all through a private company and at a fraction of a cost of other systems currently in construction.

Nasa is working on its own heavy launch system, called the SLS, but it is estimated to cost about a billion dollars per flight. SpaceX estimates that Falcon Heavy launches will cost about $90m per flight.

What’s more, just a few years ago the notion of re-landing reusable rockets seemed like a pipe dream, and yet SpaceX has made it routine, with regular landings on land and on a drone ship floating in the Atlantic Ocean. Today it managed to land two Falcon 9 rockets simultaneously, each dropping gracefully from the sky with a controlled burn.

Meanwhile, sitting in a tin can far above the earth, nothing he can do, a dummy driver in a Tesla Roadster.

An earlier photograph from inside the rocket revealed that the words “DON’T PANIC” on the dashboard computer.

In a surreal, beautiful image straight out of science fiction, the twin Falcon 9 boosters landing at Cape Canaveral in Florida, after a flawless test launch of the most powerful rocket in operation.

The drone ship is obscured in smoke and the camera cuts out thanks to vibrations from the landing burn.

But SpaceX is suggesting that this doesn’t mean anything’s amiss. Pending confirmation of landing.

Here’s another couple shots of that synchronized landing form the other two boosters: