Starship, SpaceX's massive prototype rocket that may one day send humans to Mars, achieved its first-ever ocean splashdown during its fourth flight test, a live feed showed on Thursday.

The two-stage spacecraft, consisting of the Starship cruise vessel mounted atop its towering Super Heavy rocket booster, broke apart during its last attempt in March to survive a blazingly hot reentry into Earth's atmosphere.

"Despite loss of many tiles and a damaged flap, Starship made it all the way to a soft landing in the ocean!" SpaceX CEO Elon Musk posted on social media after the splashdown.

Designed to be cheaper and more powerful than SpaceX's workhorse Falcon 9 rocket, Starship, which stands at nearly 122 meters tall, represents the future of the company's dominant satellite launch and astronaut business. NASA expects to use it in the next few years to land the first astronauts on the moon since 1972.

Each Starship rocket has made it farther in its testing objectives than previous tests before failing, either by blowing up or disintegrating in the atmosphere.

Much is riding on SpaceX's development of Starship, which NASA is relying on to return astronauts to the moon in 2026 in a rivalry with China, which plans to send its astronauts there by 2030. China has made several recent advances in its lunar program, including a second landing on the moon's far side in a sample retrieval mission named Chang'e-6.

Click here to learn more about China's space program.

Despite Starship's development appearing to be faster than other rocket programs, it has been slower than Musk originally envisioned. A Japanese billionaire who initially paid to fly Starship around the moon canceled his flight last week, citing schedule uncertainties.

And Musk's drive to rapidly build Starship has endangered SpaceX workers in Texas and California, a Reuters investigation found.

(With input from Reuters.)