Big Explosions and Big Progress in SpaceX’s 2nd Starship Launch

SpaceX, Elon Musk’s spaceflight company, launched its Starship rocket from the coast of South Texas on Saturday, a mammoth vehicle that could alter the future of space transportation and help NASA return astronauts to the moon.

Saturday’s flight of Starship, a powerful vehicle designed to carry NASA astronauts to the moon, was not a complete success. SpaceX did not achieve the test launch’s ultimate objective — a partial trip around the world ending in a splashdown in the Pacific Ocean.

But the test flight, the vehicle’s second, did show that the company had fixed key issues that arose during the earlier test operation in April. All 33 engines in the vehicle’s lower booster stage fired, and the rocket made it through stage separation — when the booster falls away and the six engines of the upper stage light up to carry the vehicle to space.

“Just beautiful,” John Insprucker, a SpaceX engineer and live launch commentator, said on the SpaceX webcast.

By contrast, the first Starship launch badly damaged the launch site; several engines on the booster failed, fires knocked out the steering of the rocket and the flight termination system took too long to explode.

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

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

Soon after stage separation, the booster exploded — a “rapid unscheduled disassembly,” in the jargon of rocket engineers. The upper-stage Starship spacecraft continued heading toward orbit for several more minutes, reaching an altitude of more than 90 miles, but then SpaceX lost contact with it after the flight termination system detonated.

In a statement, the Federal Aviation Administration said no injuries or property damage had been reported. It will conduct a mishap investigation, which is standard any time something goes wrong with a commercial rocket.

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

Starship is the biggest and most powerful rocket ever to fly. SpaceX aims to make both parts of the vehicle fully and rapidly reusable. That gives it the potential to launch bigger and heavier payloads to space and to significantly drive down the cost of…