SpaceX

SpaceX

SpaceX

SpaceX

GEAR Inc./SpaceX

Still basking in the glow of the successful launch of his first reusable rocket, Elon Musk has been sharing a few details about the demonstration flight of the company's Falcon Heavy rocket, likely coming later this year. This much-anticipated heavy lift vehicle, composed of three Falcon 9 cores, would immediately become the most powerful rocket in the world.

Perhaps the biggest tidbit is that SpaceX may try to recover the upper stage of the rocket during the launch. Composed of a single Merlin engine—a vacuum-rated version of the nine engines used on the Falcon 9 first stage—the second stage of the rocket delivers the payload to orbit after the main engines cut off. Pulling off such a recovery would be difficult but would close the company's much desired loop of reusability by bringing back the first stage, the payload fairing, and the second stage of a launch vehicle. This would essentially allow SpaceX to recycle an entire rocket.

Can it be done? It's not clear how the second stage, which reaches a much higher altitude than the first stage, would be returned to Earth. It may use some combination of the Merlin engine and parachutes, but so far the company has not specified how it will attempt such a recovery. "Odds of success low, but maybe worth a shot," Musk tweeted. Later, he added that the vehicle can be brought back to Earth like the Dragon spacecraft from orbit, but the concern is how much weight needs to be added to the second stage for a safe landing.

Musk also reiterated that the company will conduct the demonstration launch by "late summer" but acknowledged during a Thursday night news conference that flying the Falcon Heavy was a secondary priority for the company. Its first priority is launching a lengthy manifest of commercial missions on its Falcon 9 rocket. (Frankly, after years of delays, we would be excited to see a Falcon Heavy launch any time this year, whether during summer, winter, or fall.)

Explaining the delays, the founder of SpaceX said that developing the Falcon Heavy had proven more difficult than anticipated. "At first it sounded easy, but actually no this is crazy hard," Musk said. The company has had to redesign the center core and additional hardware for the upcoming flight, which he deemed to be a fairly high-risk mission. To save funds, the company plans to use two "flight proven" Falcon 9 cores as the side boosters around the center core.

As to what might launch on the Falcon Heavy, Musk playfully suggested on Twitter, "Silliest thing we can imagine!" He then went on to explain that, inspired by the suggestion of a friend and the British comedy group Monty Python's The Cheese Shop sketch, the Dragon spacecraft's demonstration flight in 2010 carried among its cargo a giant wheel of cheese. Perhaps the Falcon Heavy, too, will launch some cheesy comestibles.

Listing image by SpaceX