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24 April 2023

Why SpaceX's Starship Explosion Is No Big Deal

JEFFREY KLUGER

To hear the folks in charge tell it, you’d think that SpaceX’s Starship rocket—the biggest, grandest, most powerful rocket ever built—didn’t blow up over the Gulf of Mexico this morning, just four minutes into its maiden flight and barely 39 km (24 mi.) above ground on what was supposed to be an around-the-world orbital journey.

For one thing the company didn’t call the incident an explosion. Starship instead experienced a “rapid unscheduled disassembly” SpaceX tweeted.

For another thing, the apparent failure was met less with hung heads than high fives. “Congrats to @SpaceX on Starship’s first integrated flight test!” tweeted NASA Administrator Bill Nelson. “Every great achievement throughout history has demanded some level of calculated risk, because with great risk comes great reward. Looking forward to all that SpaceX learns, to the next flight test—and beyond.”

SpaceX founder and boss Elon Musk was no less sanguine. “Congrats @SpaceX team on an exciting test launch of Starship!” he tweeted. “Learned a lot for next test launch in a few months.”

Again, just for the record, the 40-story rocket—whose upper stage is intended to serve as the lunar landing vehicle on NASA’s crewed Artemis 3 mission in the late 2020s—blew up rather than going to space. There is no prettifying that unhappy fact. But there is no arguing with one other fact too: Blowing up or crashing is what rockets do—lots of times, over and over, throughout the history of uncrewed space flight. And this inevitable part of the testing process is essential to success in space.

On Feb. 20, 1962, John Glenn became the first American to orbit the Earth, launching aboard an Atlas rocket that had previously exploded in roughly 50% of its uncrewed test flights. On March 23, 1965, Gus Grissom and John Young strapped themselves into their Gemini 3 spacecraft, becoming the first astronauts to fly atop a Titan II intercontinental ballistic missile that had failed in more than a dozen of the test launches intended to qualify it to carry humans. On Dec. 21, 1968, Frank Borman, Jim Lovell, and Bill Anders, the Apollo 8 crew, became the first astronauts to fly the Saturn 5 moon rocket, one flight after an uncrewed Saturn 5 suffered engine failures and vibrations violent enough to nearly cause it to shake itself to pieces. But Borman, Lovell, and Anders flew anyway, becoming the first human beings to orbit the moon and returning safe and whole to Earth.

Space travel, as has been said again and again and again, is hard. And SpaceX knows that as well as anyone, following a build fast, fly fast, fail fast, and fly again R&D model that has today made it one of the world’s leading launch providers; its workhorse Falcon 9 rocket has successfully flown 217 times since 2010, including 61 launches in 2022 alone.

Falcon saw three launch failures before it became the star performer it currently is, and Starship has failed multiple times already. From 2020 to 2021, five upper stage Starship rockets were launched on short test flights—to a maximum altitude of 10 km (6.2 mi.)—four of which ended in explosions or crashes before a fifth finally succeeded, and even that one included a small fire at the base of the rocket after landing.

“That’s why we test, you know,” says Lisa Watson-Morgan, NASA’s program manager for the Artemis lunar landing system. “You learn more from a test that doesn’t go well than from one that does go well, and then you regroup and go again.

And Starship requires more of this repeated testing than most machines. The rocket is an exceedingly complex beast, with a first stage equipped with no fewer than 33 engines—an as-yet uncounted number of which seemingly did not burn during this morning’s launch. Its second stage is powered by nine engines. That, as Pablo de Leon, the chair of the department of space studies at the University of North Dakota, puts it is a “nightmare for the plumbers,” reminiscent of the Soviet Union’s 30-engine N1 moon rocket, which was intended to carry cosmonauts to the moon but is best remembered for blowing up spectacularly in a 1969 test flight, causing the largest explosion in space history.

Starship did not do nearly as badly today. The Soviet N1 erupted just seconds after liftoff, collapsing back to the ground and destroying the launch pad. SpaceX meanwhile never promised that Starship would succeed, but it did set clearing the launch tower and keeping the pad intact as one of the main goals of the mission. “Starship has cleared the pad and beach! Vehicle is on a nominal flight path,” the company tweeted in the first moments of the flight, officially marking the achievement of the modest goal it set for itself.

“I think [the explosion] was something that SpaceX anticipated as a realistic possibility,” says John Logsdon, professor emeritus and founder of the George Washington University Space Policy Institute. “They did a very good job of lowering expectations prior to the launch. And I think it’s because they realized that testing a complex system like this, there are multiple things that can go wrong. And something did.”

More still could. The company is continuing to build Starships at a furious pace—reminiscent of NASA’s Apollo era, when 13 Saturn 5s were flown from 1967 to 1973, nine of which carried crews to the moon in just a four-year window. “I think they have a factory full of multiple duplicates of these systems,” says Logsdon. “It’s not like they lost something that’s irreplaceable.”

Musk may or may not make good on his tweeted promise to launch a Starship again in a “few months,” but the company has staked its future—and NASA has staked its Artemis moon program—on the promise that the mammoth rocket will indeed fly, and fly well. Rockets explode and rockets soar. Today Starship suffered the less fortunate of those outcomes. If history is a guide, it will ultimately achieve the other.

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