"Wow, did you guys see that?"
"Starman" and the Tesla Roadster in the rocket before launch.
The rocket's two side boosters shut down, then separated as expected less than three minutes into the flight.
The video below is a replay of the live webcast. The third booster was supposed to land on a sea-faring platform called a droneship, but it wasn't immediately clear if that landing was successful.
The Falcon Heavy's demonstration flight is targeting Mars orbit, with Musk's personal red Tesla Roadster sports vehicle as the payload. In a typical Musk flourish, the auto will be blasting out David Bowie's "Space Oddity" as it leaves the atmosphere. A scrub today means it's possible Falcon Heavy could launch during a window Wednesday. Rather the next point of the Heavy would be to fire three times to send the vehicle within an elliptical orbit around the sun that goes as far out as Mars, and that auto could stay in orbit for hundreds of centuries.
There is a chance the Tesla might not make it beyond low-Earth orbit. "It would be a really huge downer if it blows up".
The payload for Musk's SpaceX rocket is a Tesla Roadster, because, why not?
"The crucial thing about Falcon Heavy and private space companies like SpaceX and others like Blue Origin is that they're driving down launch costs", Clements said.
"Every failure they have had they have bounced straight back". SpaceX has landed 21 of its Falcon 9 boosters so far.
It will generate about five million pounds of thrust during its takeoff, which, according to SpaceX, is equal to about 18 Boeing 747 airplanes. It had a liftoff thrust of 7.6 million pounds and could carry 260,000 pounds into space. The winds at high altitude are about 20 per cent stronger than the Falcon Heavy's upper limits of capability, meaning that if it was launched anyway, it would probably be torn apart or tossed back to Earth like the swiftly-binned lid from a can of baked beans.
Musk said another massive rocket under development, called BFR - short for "Big Fucking Rocket" - may be the one to transport crew, while Falcon Heavy may be reserved for equipment.
"When Falcon Heavy lifts off, it will be the most powerful operational rocket in the world by a factor of two", SpaceX boasts.
Falcon Heavy would also be able to lift twice as much as the Delta IV Heavy, now the strongest rocket, but at least one-third cheaper to make at $90 million.
The Delta IV Heavy costs about $350 million per launch, according to United Launch Alliance. The Falcon Heavy's central core, meanwhile, was sent back toward SpaceX's autonomous drone ship, Of Course I Still Love You.
"That is way, way, way below anything else in the government launch industry", Seedhouse said.
The inaugural launch of SpaceX's Falcon Heavy rocket will be a close "go" or "no go" situation.
The Soviet era Energia, which flew twice in 1987 and 1988, was also more powerful than the Falcon Heavy.
Riding on reusable rockets and spaceships - still under development - people could travel 100 at a time to the Red Planet.
NASA is also working on the Space Launch System, a rocket created to eventually take humans to Mars.