What happened during SpaceX’s Starship test flight.

Elon Musk’s SpaceX launched its Starship rocket just after 7 a.m. Central Time on Saturday from the coast of South Texas, a massive vehicle that could change the future of space transportation and help NASA return astronauts to the moon.

Starship is the largest and most powerful rocket to ever fly. SpaceX aims to make both parts of the vehicle fully and quickly reusable. That gives it the potential to launch larger and heavier payloads into space and significantly reduce the cost of putting up satellites, space telescopes, people and the things they need to live in space.

The second flight of Starship, a powerful vehicle designed to take NASA astronauts to the moon, was not a complete success. SpaceX fell short of the test launch’s ultimate goal: a partial circumnavigation of the world that ended in a landing in the Pacific Ocean.

But the flight showed that the company had resolved major issues that arose during the first test flight in April. All 33 engines in the vehicle’s lower booster stage fired, and the rocket reached phase separation – when the booster cuts out and the six upper stage engines light up to carry the vehicle to space.

“Just beautiful,” John Insprucker, a SpaceX engineer who was one of the commentators on the SpaceX webcast.

In contrast, the first Starship launch severely damaged the launch site, failed several booster engines, burned out the rocket’s controls, and took too long for the flight termination system to detonate.

In SpaceX’s “fail fast, learn faster” approach to rocket design, successfully avoiding a repeat of past failures counts as major progress.

However, the second flight revealed new challenges that Musk’s engineers must overcome.

Shortly after the stages separated, the booster exploded – a “rapid, unplanned disassembly” in the jargon of rocket engineers. The upper-stage Starship spacecraft continued toward orbit for several more minutes, reaching an altitude of more than 90 miles (150 kilometers), but then SpaceX lost contact, likely after the flight termination system exploded.

Engineers will now have to decipher what went wrong with both the booster and the upper stage spacecraft, apply fixes and then try again.

Many outside observers are optimistic that SpaceX will make Starship fully operational.

“They solved problems on their first flight and went further with this type of vehicle than ever before,” said Phil Larson, who served as a White House space adviser during the Obama administration and later worked on communications efforts at SpaceX. “The magic of engineering is that it’s all about learning, iterating on the design and moving on quickly.”

Daniel L. Dumbacher, executive director of the American Institute of Aeronautics and Astronautics, agreed. “This is a big launch system,” he said. “It’s going to take some work to get it where it needs to go. I have no doubt that the SpaceX team will be able to figure out how to make the launch vehicle work.”

The outcome of the test trip was also the final split-screen moment in the career of Mr Musk, a serial entrepreneur who previously transformed electronic payments with PayPal and electric cars with Tesla. As SpaceX prepared for the flight on Friday, Disney and Apple halted their ad spending at another of its companies, the social network X, after Musk approved an anti-Semitic post on Wednesday.