Connect with us

News

SpaceX’s Starship explosion explained by Elon Musk

The burning wreckage of Starship SN4, May 29th. (SPadre)

Published

on

Shortly after a briefing following SpaceX’s flawless astronaut launch debut, CEO Elon Musk casually revealed the best explanation yet for why a Starship prototype violently exploded during testing on May 29th.

On that fated Saturday, SpaceX successfully completed the fifth static fire of a Raptor engine installed on a full-scale Starship prototype, preceded by about an hour and a half of vehicle checks and propellant loading. Unfortunately, around a minute after Raptor shut down, what was quickly identified as liquid methane began spurting out of a specific section at the base of Starship, rapidly creating a massive cloud as the cryogenic propellant boiled and turned into gas. The specific source is unclear but moments later, something under Starship SN4 provided the shock or spark needed to ignite the expanding fire hazard, producing a spectacularly large and violent explosion.

Unsurprisingly, the accidental fuel-air explosion that was created obliterated Starship SN4 in the blink of an eye, shredding its lower (liquid oxygen) tank into steel confetti and immediately breaching the upper (liquid methane) tank, which fell to the ground and subsequently exploded again. The launch mount Starship was staged on was also damaged beyond repair and has been fully dismantled and scrapped in the two days since the anomaly. Thankfully, however, SpaceX already has replacement mounts and ships well on their way to carrying Starship SN4’s torch forward and Elon Musk already seems to understand what caused the prototype’s demise.

Shortly after a post-launch briefing celebrating and discussing SpaceX’s inaugural astronaut launch on May 30th, Reuters reporter Joey Roulette was able to ask Musk about Starship SN4’s spectacular demise the day prior. The SpaceX CEO was quoted saying that “what we thought was going to be a minor test of a quick disconnect ended up being a big problem”, confirming suspicions based on careful analysis of public views of the explosion that it was caused by issues with Starship’s ground support equipment (GSE).

Starhopper’s quick-disconnect umbilical panel is pictured here in May 2019. Starship SN4 used a similar mechanism, although the plumbing is now located inside the vehicle’s circumference. (NASASpaceflight – bocachicagal)

In Musk’s statement, “quick disconnect” (QD) refers to an umbilical port that connects a launch vehicle to GSE, enabling the loading and offloading of propellant and fluids, clamping down the rocket, and providing a wired telemetry and communications link for ground controllers. QDs must perform all those tasks while also being able to rapidly release and disconnect, allowing the rocket to lift off while still protecting its sensitive ports for ease of reuse.

In theory, Starship’s quick-disconnect umbilical panel is even more complex, as it will have to simultaneously enable the ship to be fueled and controlled while sitting on top of a Super Heavy booster and permit in-orbit docking and refueling. Given that Starships are currently being tested independently on spartan launch mounts, it’s unclear if the current generation of prototypes has been outfitted with advanced QD panels. More likely, Musk was referring to a test of a less advanced QD panel similar to the rough version used on Starhopper last year, and SpaceX simply wanted to test its ability to disconnect and reconnect to Starship on command.

SpaceX’s existing Starship launch mount was heavily damaged by SN4’s explosion and has since been fully dismantled. (NASASpaceflight – bocachicagal)
Starship SN4’s remains have already been cleared from the pad. (NASASpaceflight – bocachicagal)

If that’s the case, the likeliest explanation for SN4’s explosion is that that quick disconnect was unable to fully reconnect after the test, resulting in a leak from the liquid methane port when SpaceX began to detank the rocket. Instead of the highly-pressurized fluid flowing smoothly back to ground storage tanks, the liquid methane sprayed wildly, akin to the effect one might observe when attempting to block off an active water source with an open palm.

Work on a second launch mount was already ongoing when Starship SN4 exploded on May 29th. (NASASpaceflight – bocachicagal)
Starship SN5 and SN6 are simultaneously being assembled in SpaceX’s new vertical assembly building (VAB). (NASASpaceflight – bocachicagal)

Compared to the many possible ways a fueled Starship could fail, a propellant leak started by a faulty umbilical panel is about as convenient as they come. Starship SN4 may have been violently destroyed as a result, turning a relatively small error into exceptionally painful lesson but SpaceX has already had some success building full-scale prototypes at an almost unbelievably low cost – likely less than $10M apiece. Starship SN5 appears to be just shy of ready to take SN4’s place on the launch mount, although SpaceX will have to build an entirely new launch mount before it can resume testing.

At the same time, Starship SN5’s successor – SN6 – is just one stacking event away from reaching a level of completion similar to SN4 and SN5. All told, Starship SN4’s demise is just another part of the process of developing a new kind of rocket by building and testing hardware – failure can be a valuable tool when managed properly. Based on past observations, SpaceX could be ready to continue testing (and hopefully flying) Starship prototypes before the end of the month.

Advertisement
-

Check out Teslarati’s Marketplace! We offer Tesla accessories, including for the Tesla Cybertruck and Tesla Model 3.

Eric Ralph is Teslarati's senior spaceflight reporter and has been covering the industry in some capacity for almost half a decade, largely spurred in 2016 by a trip to Mexico to watch Elon Musk reveal SpaceX's plans for Mars in person. Aside from spreading interest and excitement about spaceflight far and wide, his primary goal is to cover humanity's ongoing efforts to expand beyond Earth to the Moon, Mars, and elsewhere.

Advertisement
Comments

Elon Musk

Elon Musk roasts India’s billionaire Mukesh Ambani as Starlink fight heats up

Elon Musk sarcastically calls Mukesh Ambani ‘Prime Minister’ as the Starlink India standoff escalates again.

Published

on

By

Elon Musk escalated his public fight over Starlink’s launch in India on Friday, addressing Reliance chairman Mukesh Ambani as “Prime Minister Ambani” in a sarcastic post on X. “Please accept my humble apologies for not realizing that you are the real boss of India,” Musk wrote, before accusing Ambani of “monopolistic exploitation” and asking whether he would “consider allowing Starlink to compete.” In follow up posts, he said Starlink has proven essential during natural disasters and would help parts of India with no internet access.

The post came two days into a fight that Musk sparked up on Wednesday, when he said Starlink was “being blocked by certain oligarchs in order to maintain their monopolistic chokehold on the Indian people.” He called it “a crime against the people of India” and left the names out, adding only, “You can guess who they are.” Jio and Airtel together hold more than 80% of India’s telecom market. On Thursday, Musk asked whether Ambani is “the real boss of India” and said Starlink has spent five years complying with “every single law and requirement” of the Indian government.

India’s government has pushed back each time. The Ministry of Communications called the suggestion that its framework is unfair or discriminatory “baseless and misconceived.” Communications Minister Jyotiraditya Scindia said Friday that three companies hold satcom licenses: Starlink, Jio Satellite Communications, and Bharti backed Eutelsat OneWeb. Amazon’s Kuiper, now Amazon Leo, is still going through the process. None can launch until regulators finalize satellite spectrum pricing and the Home Ministry signs off on each company’s security compliance. Scindia said the telecom regulator and the Department of Telecommunications are close to a decision on pricing, The Hindu reported. Bharti chairman Sunil Mittal also said OneWeb is still waiting on approvals.

Starlink received its operator license in 2025 after a three year wait, and the space regulator IN-SPACe granted what industry executives called the last approval needed in July. The holdup since then centers on security, particularly concern that foreign operators could bypass Indian gateways.

Musk and Ambani have been on opposite sides of this before. In late 2024, Ambani argued for auctioning satellite spectrum, which Musk criticized as out of step with the rest of the world, and India chose administrative allocation instead. By March 2025, the two sides had signed a deal to sell Starlink devices in Reliance stores, and Starlink secured its telecom license that June. That partner is now also a competitor. Jio is reportedly weighing a constellation of 1,600 to 1,650 satellites costing an estimated $10 billion to $15 billion, while Akash Ambani has told shareholders Jio plans to lease capacity from global providers to move quickly.

Continue Reading

Elon Musk

Elon Musk’s surprise addition to the X Takeover lineup has fans talking

Elon Musk will join Saturday’s X Takeover at Giga Texas for a live virtual interview.

Published

on

By

Credit: Tesla Owners Silicon Valley
Credit: Tesla Owners Silicon Valley

Elon Musk will join X Takeover at Giga Texas on Saturday for a live virtual interview, according to Sawyer Merritt, who shared the news late Thursday. Musk will not be on stage in Austin. The conversation is set to stream for free on the @teslaownersSV account on X.

Organizers had kept expectations in check. In a September update, Tesla Owners Silicon Valley said Musk had appeared at the event twice before but was not promising a third appearance, even as fans hoped he would walk the Giga Texas grounds in person. A virtual spot matches 2024, when Musk gave a surprise interview of about an hour to the crowd in San Luis Obispo, as Teslarati reported at the time.

This year’s edition is a first in several ways. It is the first X Takeover held outside California and the first at a Tesla facility, with tickets selling out in eight days. Tesla provides the venue, but the event is produced independently by Tesla Owners Silicon Valley. The main event runs from 10 a.m. to 6 p.m. CT, followed by a drone and light show at 9 p.m. Maye Musk is the keynote speaker, Franz von Holzhausen is set for a virtual keynote, and Nicki Minaj is the special guest. Joe Tegtmeyer, whose drone footage Teslarati used to track the Optimus factory steel frame at Giga Texas, is also on the speaker list.

Musk’s interview topics have not been revealed, but the backdrop is busy. Tesla doubled its Cybercab fleet in Austin in late September, and last week Musk explained why Robotaxi hours only moved from 10 p.m. to 11 p.m.. Merritt also reported Thursday that Texas DMV records now show 319 registered Cybercabs, up from 169. NHTSA’s deadline for Tesla’s sworn answers on Cybercab certification is October 30, and Tesla reports third quarter earnings on October 21.

Fans who cannot make it to Austin can watch the livestream on X. Musk tends to say more in unscripted settings than he does in prepared remarks, which is the reason this one is worth having open on Saturday.

Continue Reading

News

It’s official: SpaceX takes aim at Verizon, AT&T, and T-Mobile

SpaceX is buying 800 MHz spectrum from Grain to turn Starlink Mobile into a carrier.

Published

on

By

Starlink D2D direct to device vs Verizon, AT&T (Concept render by Grok)

SpaceX has agreed to buy a nationwide block of low band wireless spectrum, a deal the company says will let Starlink Mobile operate as a full US carrier rather than a satellite add-on for someone else’s network.

The company announced the agreement on X on Thursday afternoon, saying it will “pave the way for @Starlink to become a major mobile carrier in the US.” The seller is Grain Management, a private investment firm that confirmed in a statement that SpaceX will acquire 100% of its nationwide 800 MHz portfolio. That covers up to 14 MHz of paired spectrum in the 817 to 824 MHz and 862 to 869 MHz bands. Neither side disclosed a price, and the deal still needs FCC approval.

Grain only recently picked up the licenses itself. It bought the portfolio from T-Mobile in a transaction that closed in August, paying cash plus its own 600 MHz spectrum. Rival AST SpaceMobile had been testing satellites on the same bands before SpaceX stepped in.

SpaceX said its 2 GHz spectrum will handle high bandwidth capacity, while the new 800 MHz layer “ensures Starlink Mobile’s signal penetrates through obstacles, such as walls, and can provide service to customers’ devices even when they are in buildings.” The company added that most existing phones already support the band, so customers would not need new hardware to use it.

That 2 GHz spectrum came from SpaceX’s EchoStar acquisition last year, which gave the company exclusive S band rights in the US and global Mobile Satellite Service licenses. The Grain spectrum is different in an important way: it is tailored for service from ground towers, not satellites. SpaceX said that combination would make Starlink Mobile “the first network operator to deploy both satellite and terrestrial spectrum.”

The announcement also follows a key regulatory win. Earlier this week, the FCC approved SpaceX’s plan to deploy 15,000 second generation Starlink Mobile satellites, which the company has said will carry up to 100 times the data density of the current system, as Teslarati previously reported.

Shares of AT&T, Verizon and T-Mobile fell in extended trading after the announcement. T-Mobile is currently SpaceX’s launch partner for Starlink Mobile in the US, which makes its position the most complicated of the three.

SpaceX has not been subtle about its plans. During the company’s August earnings call, President and COO Gwynne Shotwell said she expected Starlink Mobile to win over customers from the major carriers. “I anticipate us to be able to acquire quite a few of their customers because I think our service will be better,” she said, pointing to dead zone coverage and resilience during disasters. Shotwell also described plans for low cost cellular base stations that could pair with existing Starlink dishes.

SpaceX has targeted 2027 for deployment of its next generation Starlink Mobile satellites, with upgraded service expected by the end of that year. The FCC review of the Grain deal now determines when the terrestrial half of that network can come online.

Continue Reading