FLORIDA, USA (AP) — SpaceX’s big new rocket blasted off yesterday on its first test flight, carrying a red sports car aiming for an endless road trip past Mars.

The Falcon Heavy rose from the same launch pad used by NASA nearly 50 years ago to send men to the moon. With lift-off, the Heavy became the most powerful rocket in use today, doubling the lift-off punch of its closest competitor.

The three boosters and 27 engines roared to life at Kennedy Space Center, as thousands jammed surrounding beaches, bridges and roads to watch the rocket soar, delayed more than two hours by high wind.

Two of the boosters were recycled and programmed to return for a simultaneous touchdown at Cape Canaveral, while the third, brand new, set its sights on an ocean platform some 300 miles offshore.

SpaceX chief executive Elon Musk owns the rocketing Tesla Roadster, which is shooting for a solar orbit that will reach all the way to Mars. As head of the electric carmaker Tesla, he combined his passions to add a dramatic flair to the Heavy’s long-awaited inaugural flight. Typical ballast for a rocket debut: concrete or steel slabs, or experiments.

On the eve of the flight, Musk told reporters the company had done all it could to maximise success and he was at peace with whatever happens: success, “one big boom” or some other calamity. The longer the flight, he noted, the more the company would learn from the heavily instrumented rocket.

Musk has plenty of experience with rocket accidents, from his original Falcon 1 test flights to his follow-up Falcon 9s, one of which exploded on a nearby pad during a 2016 ignition test. The Falcon Heavy is a combination of three Falcon 9s, the rocket that the company uses to ship supplies to the International Space Station and lift satellites. Spacex is reusing first-stage boosters to save on launch costs.

The Heavy is intended for massive satellites like those used by the US military and major-league communication companies. Even before the test flight, customers were signed up.

Given the high stakes and high drama, Tuesday’s launch attracted huge crowds not seen since NASA’s last space shuttle flight seven years ago. While the shuttles had more lift-off muscle than the Heavy, the all-time leaders in both size and might were NASA’s Saturn V rockets, which first flew astronauts to the moon in 1968.

Not counting Apollo moon buggies, the Roadster is the first automobile to speed right off the planet.

At the convertible’s wheel is SpaceX’s “Starman”, a dummy in a white-and-black-trimmed spacesuit, and on the soundtrack is another nod to David Bowie: his 1969, pre-Apollo 11 song “Space Oddity,” featuring the memorable line “Ground Control to Major Tom.” SpaceX is hoping for live shots of the car from on-board cameras, once the protective enclosure comes off and the car sails off fully exposed.

The car faces considerable speed bumps before settling into its intended orbit around the sun, an oval circle stretching from the orbit of Earth on one end to the orbit of Mars on the other.

First, the Roadster needed to survive lift-off, no small feat for a rocket hot off the factory floor. Then it has to endure a cosmic bombardment on its several hours of cruising through the highly charged Van Allen radiation belts encircling Earth. Finally, a thruster has to fire to put the car on the right orbital course.

If it weathers all this, the Roadster will reach the vicinity of Mars in six months, Musk said. The car could be travelling between Earth and Mars’ neighbourhoods for a billion years, according to the high-tech billionaire.

Musk acknowledged the Roadster could come “quite close” to Mars during its epic cruise, with only a remote chance of crashing into the red planet.

Win or lose, the Heavy already is rattling the launch market. Its sticker price is US$90 million, less than one-tenth the estimated cost of NASA’s Space Launch System megarocket in development for moon and Mars expeditions.

SpaceX has decided against flying passengers on the Heavy, and Musk told reporters Monday, and instead will accelerate development of an even bigger rocket to accommodate deep-space crews. His ultimate goal is to establish a city on Mars.