In a reply to another user's tweet, the tech mogul explained that each fairing has its own avionics system and nitrogen thrusters, as well as steerable parachutes, to help them return to Earth safely. The nosecone halves don't have great aerodynamics, and SpaceX has been testing various ways of recovering them for many months.
The fairing is a piece of material that's part of the rocket's nosecone, protecting the payload, which can include things like satellites, during launch.
SpaceX has two operational rockets: the Falcon 9, which with 21 launches in 2018 dominates the U.S. market, and the Falcon Heavy, which as its name suggests is created to lift much heavier payloads into more distant orbits.
And that wasn't the only first for SpaceX. Because it flies higher and reaches faster speeds than the side boosters, landing it is a trickier endeavor, one SpaceX missed on Falcon Heavy's last test flight in 2018.
SpaceX is hoping that, with Heavy's first commercial flight under its belt, it can increase the frequency with which the massive rocket blasts off.
On March 13th, NASA administrator Jim Bridenstine told lawmakers at a Senate hearing that the agency was mulling over the idea of using a commercial rocket, potentially the Falcon Heavy, to launch an important test flight around the Moon.
"Three for three boosters today", a SpaceX webcast commentator said.
This is Falcon Heavy's second launch.
The lift-off was crucial in the race with Boeing-Lockheed venture United Launch Alliance and Mr Jeff Bezos' Blue Origin as SpaceX aims to clinch a third of all US National Security Space missions - coveted military contracts worth billions.
This was followed two minutes later by the core booster landing at sea aboard the company's droneship, Of Course I Still Love You, which was parked at sea 990 km (615 miles) off the coast of Cape Canaveral. These boosters have been part of the Falcon 9 rocket for nearly a year and offer better thrust, improved landing legs and other features that make retrieval easier.