Amid cheers from SpaceX employees on the livestream, the rocket took off on a pillar of smoke.
The Falcon Heavy is propelled by 27 engines contained in three boosters — two on the sides, and one in the center under the payload.
The three boosters gave the rocket a lot of power — they're capable of generating more than 5 million pounds of thrust.
After the ascent, the two side boosters detached successfully from the rocket, flipped around, and headed back down toward Florida.
The two bottom screens in this shot from the video stream show the boosters heading toward each of their landing sites.
A few seconds later, the re-usable boosters slowed themselves down and hit the ground.
They even stuck the landing.
Later, the center booster detached, leaving the Tesla Roadster, complete with a dummy driver named "Starman" wearing a SpaceX spacesuit, speeding toward Mars orbit.
Three cameras are attached to the Roadster, showing views of Starman as he heads out into space. The dummy is reminded not to panic by a sign on the dashboard.
SpaceX is broadcasting a live video feed from the Roadster if you'd like to see more of the journey.
You can re-watch the entire launch here.
