SpaceX engineers mounted a Starship second-stage rocket on top of a Super Heavy booster with extreme caution, resulting in the world's highest rocket, albeit one that has yet to leave Earth's surface.

The freshly built Starship system stands 394 feet tall, taller than NASA's Saturn V rocket from the Apollo period (362.9 feet) and NASA's future SLS rocket when stacked in the Block 2 cargo configuration (365.1 feet). Elon Musk, the CEO of SpaceX, excitedly tweeted photos of the massive structure, characterizing it as a "Starship Fully Stacked."

SpaceX transported the rocket BN4 to the launch mount earlier this month. After engineers installed all 29 Raptor engines, Science Times said Elon Musk shared the rocket's bottom in a spectacular shot. The rocket's top and bottom sections are each 9 meters(30 feet) broad. Meanwhile, the Super Heavy standing at 70 meters (230 feet) and the Starship at 50 meters (160 feet).

More Work to Do For SN20

SpaceX also dismantled SN20and returned to the hangar for additional repair. SpaceX plans to launch the vehicle later this year, as Science Times reported.

There is still much work to do before this behemoth takes to the sky. Ground testing of the system, including fuelling, pressurization, and static firing, is still required by SpaceX. SpaceNews said there's that environmental study being completed by the US Federal Aviation Administration, which means the entire project is in limbo until the conclusions are revealed.

(Photo: PATRICK T. FALLON/AFP via Getty Images)
The recovered first stage of a Falcon 9 rocket stands at Space Exploration Technologies Corp. (SpaceX) on February 2, 2021, in Hawthorne, California. - Inspiration4 mission commander Jared Isaacman, founder and chief executive officer of Shift4 Payments all-civilian Inspiration4 mission, will raise $200 million for St. Jude Children's Research Hospital through a donation-based sweepstakes to select a member of the crew.

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This uncertainty hasn't deterred Musk, who recently tweeted, "Starbase is progressing at Warp 9," about the Boca Chica launch facility's development. The firm is constructing the Orbital Launch Site (OLS), launching and landing the Starship system. According to NASA Spaceflight, the pace of work at the Texas plant has accelerated considerably in recent weeks, with hundreds of personnel being pulled in from other SpaceX locations around the country. NASA chose SpaceX to build a Moon lander for the future Artemis missions might explain the frantic pace, Science Times reported.

Super Heavy Booster: SpaceX's "Most Powerful" Launch Vehicle Yet

Gizmodo said SpaceX would fire up the BN4 Super Heavy booster for around two minutes (169 seconds) before the second-stage Starship portion separates during the stacked Starship system's intended first orbital test. The rocket will fall 20 miles (32 kilometers) from the launch site and land in the Gulf of Mexico. Before making a full revolution, the starship will restart its voyage, reach Earth orbit, and re-enter. The SN20 starships will arrive near Kauai, Hawaii.

The stainless steel rocket will be one of the most powerful launch vehicles SpaceX has ever built when it is finished. It is capable of carrying 150 tons into orbit. The rocket will use subcooled liquid methane and liquid oxygen fuel during liftoff and exert 16,190,000 pounds (72 meganewtons) thrust.

Both components will eventually be able to land vertically on their own. After numerous failed attempts, SpaceX finally succeeded in landing a Starship prototype on May 5, 2021. However, they were suborbital testing; Starship will have to withstand Mach 25 speeds and the accompanying heat during orbital re-entry, then land. The Super Heavy is supposed to land on six legs, but SpaceX plans to capture the rocket at the OLS tower using a different method.

SpaceX envisioned Starship as a reusable system capable of delivering people and cargo to Earth orbit, the Moon, and Mars. SpaceX is presently working on a contract with NASA to showcase a modified crew-rated Starship vehicle for the future Artemis lunar missions.

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Check out more news and information on SpaceX in Science Times.