SpaceX’s massive rocket Starship explodes 4 minutes after liftoff

SpaceX on April 20 tested its next-generation rocket designed for missions to the moon and Mars, ending in an explosion amid cheers from employees who gathered to watch a livestream of the launch.

The uncrewed rocket ignited and blasted skyward for about four minutes, but the separation of the booster from the spacecraft that sat atop the rocket appeared to fail. Some of the booster's 33 engines appeared to not ignite, NBC News reports.

The rocket then began to tumble downward before exploding.

The cause of the explosion and failure of the separation was not immediately known, though the rocket's blast-off already meant the test was considered by the company to be a success.

"As if the flight test was not exciting enough, Starship experienced a rapid unscheduled disassembly before stage separation," SpaceX tweeted shortly after the test. "Teams will continue to review data and work toward our next flight test."

The rocket — the most powerful ever developed — is set to play a key role in NASA's Artemis program, which plans to put humans on the moon in 2025.

Thursday's test flight launched SpaceX's Starship spacecraft with nobody aboard for a planned 1½-hour flight. Starship is meant to be a reusable vehicle capable of carrying massive cargo loads into space.

The company had emphasized that the test was an early step.

"Congrats @SpaceX team on an exciting test launch of Starship!" SpaceX CEO Elon Musk tweeted. "Learned a lot for next test launch in a few months."

The test flight is the biggest step yet for SpaceX efforts to create a reusable spacecraft that can fuel space exploration that goes beyond current limitations. And while the rocket and its spacecraft are designed to be recoverable, Thursday's test planned for them to fall into the ocean.

The test is meant to collect data on the system's performance, which is crucial for future development.