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SpaceX’s gargantuan deep-space rocket system, Starship, touched down safely Saturday morning but ended prematurely with an explosion and loss of signal.
The Super Heavy booster managed to separate from the Starship after takeoff, when the Starship fired its engines and pushed away. That process ended up destroying the Super Heavy booster in a ball of flames over the Gulf of Mexico. But the Starship spacecraft was able to briefly continue its journey.
The Starship system made it much further into flight than the first attempt in April. The rocket and spacecraft lifted off from the launch pad at 8 a.m. ET, with the Super Heavy booster firing all 33 Raptor engines. Even during ground tests, SpaceX has had trouble consistently powering all those engines, which are clustered together at the bottom of the rocket, at the same time.
The upper stage Starship had begun its journey on Saturday morning strapped to the top of the first stage Super Heavy, a rocket 232-feet high (70.7-meter-high). About two and a half minutes after it went live and slid away from the launch pad, the Super Heavy booster spent most of its fuel, and the Starship spacecraft fired its own engines and broke away.
The Starship spacecraft used its own six engines to continue propelling itself to faster speeds. SpaceX aimed to launch the spacecraft to orbital velocities, typically around 17,500 miles per hour (28,000 kilometers per hour). A starship climbed to a height of about 93 miles (150 kilometers) above Earth’s surface, reaching the edge of space.
The US government considers the edge of outer space to be 50 miles (80 kilometers) above the Earth’s surface. Internationally, the Kármán line, located 62 miles (100 kilometers) above sea level, is often used to mark the boundary between our planet and space – but there are many gray areas.
The SpaceX team was waiting for a signal from the spacecraft, but it was shared during the live stream that “the second stage was lost.”
“The automated flight termination system appears to have pulled on the second stage very late in the burn as we were descending in range out over the Gulf of Mexico,” said aerospace engineer John Insprucker.
The flight termination system used by SpaceX to prevent the starship from traveling off course is essentially a self-destruct feature.
“An unscheduled rapid disassembly of the booster occurred shortly after stage separation and Starship’s engines burned for several minutes en route to space,” SpaceX is divided into X, formerly known as Twitter. “With testing like this, success comes from what we learn, and today’s test will help us improve the reliability of Starship as SpaceX strives to make life multiplanetary.”
The Federal Aviation Administration, which approved Starship’s test flight today, issued a statement following the test flight.
“A disaster occurred during the launch of SpaceX Starship OFT-2 from Boca Chica, Texas, on Saturday, November 18. The vehicle was lost as a result of the anomaly. No injuries or damage to public property were reported,” an FAA spokesperson said.
The agency will conduct a disaster investigation to determine the root cause of the Starship loss, which is standard procedure.
“The Starship Super Heavy vehicle has returned to flight based on the FAA’s determination that no system, process or procedure related to the disaster affects public safety,” according to the FAA.
It took more than four months for the FAA to complete the final disaster investigation after the Starship test flight in April.
NASA is investing up to $4 billion in the rocket system with the goal of using the Starship capsule to transport astronauts to the surface of the moon for its Artemis III mission, which is currently scheduled to lift off as early as 2025.
The effort aims to return humans to the moon for the first time in five decades, and the successful completion of this test flight would bring the US space agency and SpaceX one step closer to that goal.
“Congratulations to the teams who made progress on today’s flight test,” NASA Administrator Bill Nelson shared on X. “Spaceflight is a daring adventure that requires a talented spirit and dazzling innovation. Today’s test is an opportunity to learn – then fly again. Together @NASA and @SpaceX will return humanity to the Moon, Mars and beyond.”
“Each test shows a step closer to putting the first woman on the Moon with the #Artemis III Starship human landing system. Looking forward to seeing what can be learned from this test that moves us closer to the next milestone,” Jim Free, NASA’s associate administrator for exploration systems development, divided by X.
The failure of Starship development and the production of the main missions together, especially NASA’s Artemis III mission, could lead to significant delays. The US space agency tapped Starship in 2021 to serve as the lunar lander for that mission.
Hot staging process
The root cause of the failure of the Starship rocket on Saturday was not immediately clear.
But the booster explosion occurred after a phase known as “hot staging” that SpaceX attempted for the first time on Saturday.
The method was used to separate the Starship spacecraft and Super Heavy rocket after liftoff.
Almost all rockets go through a process during launch called “phase separation,” in which the lowest rocket booster separates from the rest of the rocket or spacecraft.
When SpaceX launched its workhorse Falcon 9 rocket, for example, the first-stage booster — or the lower part of the rocket — broke off from the upper part of the rocket less than three minutes after it took off. The Falcon 9 does so by using an air duster located within the rocket’s interstage, or black band around the center.
Instead, the Starship spaceship fired up its own engines to push itself away from the Super Heavy booster – and is essentially torn apart by blunt force trauma.
It was a big time for SpaceX, as the hot staging was expected to be “the most dangerous part of the flight,” SpaceX CEO Elon Musk said in October.
SpaceX had already said that it would consider the mission a success if Starship successfully completed the hot staging.
But after a hot stage, the Super Heavy booster began to fall out of control and exploded over the Gulf of Mexico moments later. SpaceX hoped to restore the Super Heavy’s engines and guide it to a controlled landing.
“We knew the hot staging would be extremely dynamic,” said Kate Tice, senior manager of SpaceX Quality Systems Engineering, during the live stream. We knew there was a chance the booster wouldn’t last, but we’re going to take that data and figure out how we can improve the booster for the next hot phase.”
At first, the Starship spaceship continued to move forward after separation.
About eight minutes after liftoff, cheers could be heard echoing through mission control as the Starship neared the end of its engine burn – setting it on a path toward Earth orbit. But nine minutes after launch, SpaceX made it clear that it had lost a video signal with Starship.
About 11.5 minutes into the flight, the company confirmed that it had lost data, indicating that Starship was not flying as planned. Then, the spacecraft’s flight termination system was activated to prevent it from going off course, bringing the test flight to an early end.
If all had gone according to plan,Starship would have continued to accelerate towards space. The Starship spacecraft was then slated to complete nearly one full bite of Earth, aiming to splash down in the Pacific Ocean near Hawaii.
The destruction of the vehicle shortly after liftoff was a reminder of the Starship’s first launch attempt in April. During that test flight, several of the Super-Heavy’s engines unexpectedly powered up and the rocket began to spin out of control just minutes after liftoff. SpaceX was forced to trigger the system’s self-destruct feature, blowing up both stages over the Gulf of Mexico.
It took SpaceX several months to recover from the April disaster. The company had to rebuild its launch site, which had been torn to pieces by the sheer force of the rockets driving its engines. The company also implemented upgrades to the Starship spacecraft and the Super Heavy booster.
SpaceX typically includes fiery disasters in the early stages of rocket development. The company has long argued that it can learn to build a better rocket faster and cheaper by flying early prototypes — and sometimes exploding — rather than relying entirely on ground testing and computer modeling.
After the first explosive test flight in April, SpaceX noted that “Success comes from what we learn, and we learned a lot.”
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