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SpaceX Starship stacked with ballast for hop test debut

Starship SN4 has been outfitted with a ballast weight to enable its inaugural flight test. (NASASpaceflight - bocachicagal)

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SpaceX has installed a custom-built ballast atop its fourth full-scale Starship prototype, a sign that the company is rapidly approaching the ship’s first Starhopper-style hop test.

Although CEO Elon Musk officially “redirected” SpaceX’s resources away from Starship’s first flight and towards Crew Dragon’s NASA astronaut launch debut, the company continues to work around the clock to ready Starship SN4 for the program’s biggest test yet. Designed with the goal of creating a fully-reusable, ultra-capable launch vehicle that is unprecedentedly affordable, SpaceX’s Starship spacecraft and Super Heavy booster have made impressive progress over the last 12 or so months.

In July and August 2019, Starhopper – a low-fidelity testbed and proof of concept – successfully performed two untethered hop tests, ultimately flying more than 150m (~500 ft) above ground before safely touching down. Three months later, the first full-scale Starship prototype was destroyed almost immediately after its first pressure test began, a failure that lead SpaceX to expedite factory upgrades. Just six months later, SpaceX has completed multiple successful tests, including pressure tests that pushed beyond the pressures needed for safe human spaceflight, several full wet dress rehearsals (WDRs) with live propellant, and three Raptor engine static fires. In fewer words, Starship is ready for its next big test: flight.

SpaceX technicians prepare to complete a jerryrigged ballast weight for Starship SN4. (NASASpaceflight – bocachicagal)

However, Starship SN4 currently has just one Raptor engine installed and will remain in that configuration for its inaugural hop, expected to reach a maximum altitude identical to Starhopper (150m/500ft). The odd configuration means that the rocket will be propelled by asymmetric thrust, as Starship’s ‘thrust puck’ engine section is designed to hold three Raptor engines in a triangular formation. Raptor is capable of producing up to 200 metric tons (~440,000 lbf) of thrust with an unclear level of throttle control (likely mediocre according to comments made by Elon Musk).

Impressively, although it might seem reasonable to assume that Starship SN4 is about as heavy as the ~120 ton Starhopper, the clear and present need to install substantial ballast suggests otherwise. Combined with comments made during SN4’s April 2020 transport from factory to launch site, it appears that even SpaceX’s early Starship engine sections weigh just 50-60 metric tons (110,000-125,000 lb) empty. That weight doesn’t account for the flaps, heat shield, nose section, or many other heavy components that orbital Starships will eventually need but is still impressive.

Starship SN4 was transported to the launch pad on April 23rd. (NASASpaceflight – bocachicagal)
On May 27th, SpaceX installed a massive ballast weight on top of the Starship prototype. (NASASpaceflight – bocachicagal)

That impressive weight reduction, Raptor’s inability to safely throttle low, and the FAA’s lack of interest in dozens (up to hundreds) of tons of explosive propellant flying above or around populated areas poses its own challenges for the first full-scale Starship flight. The addition of ballast helpfully solves (or at least alleviates) several of those issues. Notably, ballast can prevent SpaceX from having to fuel Starship SN4 with dozens of extra tons of explosive propellant to counteract the high thrust of its single engine and permit a safe launch and landing.

At the same time, if Starship SN4’s wet weight is reduced by carrying less propellant during its first flight, that actually exacerbates the problem of Raptor’s small throttle range, as a lighter ship would be much harder to manage as the engine rapidly burns propellant and thus loses mass. With ballast, Raptor won’t have to throttle as low as it would otherwise have to to ensure a gentle rate of deceleration. Built out of sheet steel and two spare rolls of the same steel used to form Starship rings, Starship SN4’s new ballast likely increases its dry mass by some 50% or more (25+ metric tons).

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(NASASpaceflight – bocachicagal)
Starship SN4’s solid steel ballast. (NASASpaceflight – bocachicagal)

Pending Crew Dragon’s inaugural astronaut launch, now scheduled no earlier than 3:22 pm EDT (19:22 UTC), May 30th after weather delayed the first May 27th launch attempt, Starship SN4 has no testing periods on the calendar at the moment. Speaking around May 23rd, Musk stated that the ship was likely at least a “few weeks” away from its flight debut, suggesting that the ship will perform another static fire test to prepare for its first hop as early as next week. Stay tuned for updates as SpaceX’s works towards two very exciting Crew Dragon and Starship milestones.

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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.

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Tesla’s Elon Musk: 10 billion miles needed for safe Unsupervised FSD

As per the CEO, roughly 10 billion miles of training data are required due to reality’s “super long tail of complexity.” 

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Credit: @BLKMDL3/X

Tesla CEO Elon Musk has provided an updated estimate for the training data needed to achieve truly safe unsupervised Full Self-Driving (FSD). 

As per the CEO, roughly 10 billion miles of training data are required due to reality’s “super long tail of complexity.” 

10 billion miles of training data

Musk comment came as a reply to Apple and Rivian alum Paul Beisel, who posted an analysis on X about the gap between tech demonstrations and real-world products. In his post, Beisel highlighted Tesla’s data-driven lead in autonomy, and he also argued that it would not be easy for rivals to become a legitimate competitor to FSD quickly. 

“The notion that someone can ‘catch up’ to this problem primarily through simulation and limited on-road exposure strikes me as deeply naive. This is not a demo problem. It is a scale, data, and iteration problem— and Tesla is already far, far down that road while others are just getting started,” Beisel wrote. 

Musk responded to Beisel’s post, stating that “Roughly 10 billion miles of training data is needed to achieve safe unsupervised self-driving. Reality has a super long tail of complexity.” This is quite interesting considering that in his Master Plan Part Deux, Elon Musk estimated that worldwide regulatory approval for autonomous driving would require around 6 billion miles. 

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FSD’s total training miles

As 2025 came to a close, Tesla community members observed that FSD was already nearing 7 billion miles driven, with over 2.5 billion miles being from inner city roads. The 7-billion-mile mark was passed just a few days later. This suggests that Tesla is likely the company today with the most training data for its autonomous driving program. 

The difficulties of achieving autonomy were referenced by Elon Musk recently, when he commented on Nvidia’s Alpamayo program. As per Musk, “they will find that it’s easy to get to 99% and then super hard to solve the long tail of the distribution.” These sentiments were echoed by Tesla VP for AI software Ashok Elluswamy, who also noted on X that “the long tail is sooo long, that most people can’t grasp it.”

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Tesla earns top honors at MotorTrend’s SDV Innovator Awards

MotorTrend’s SDV Awards were presented during CES 2026 in Las Vegas.

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Credit: Tesla China

Tesla emerged as one of the most recognized automakers at MotorTrend’s 2026 Software-Defined Vehicle (SDV) Innovator Awards.

As could be seen in a press release from the publication, two key Tesla employees were honored for their work on AI, autonomy, and vehicle software. MotorTrend’s SDV Awards were presented during CES 2026 in Las Vegas.

Tesla leaders and engineers recognized

The fourth annual SDV Innovator Awards celebrate pioneers and experts who are pushing the automotive industry deeper into software-driven development. Among the most notable honorees for this year was Ashok Elluswamy, Tesla’s Vice President of AI Software, who received a Pioneer Award for his role in advancing artificial intelligence and autonomy across the company’s vehicle lineup.

Tesla also secured recognition in the Expert category, with Lawson Fulton, a staff Autopilot machine learning engineer, honored for his contributions to Tesla’s driver-assistance and autonomous systems.

Tesla’s software-first strategy

While automakers like General Motors, Ford, and Rivian also received recognition, Tesla’s multiple awards stood out given the company’s outsized role in popularizing software-defined vehicles over the past decade. From frequent OTA updates to its data-driven approach to autonomy, Tesla has consistently treated vehicles as evolving software platforms rather than static products.

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This has made Tesla’s vehicles very unique in their respective sectors, as they are arguably the only cars that objectively get better over time. This is especially true for vehicles that are loaded with the company’s Full Self-Driving system, which are getting progressively more intelligent and autonomous over time. The majority of Tesla’s updates to its vehicles are free as well, which is very much appreciated by customers worldwide.

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Elon Musk

Judge clears path for Elon Musk’s OpenAI lawsuit to go before a jury

The decision maintains Musk’s claims that OpenAI’s shift toward a for-profit structure violated early assurances made to him as a co-founder.

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Gage Skidmore, CC BY-SA 4.0 , via Wikimedia Commons

A U.S. judge has ruled that Elon Musk’s lawsuit accusing OpenAI of abandoning its founding nonprofit mission can proceed to a jury trial. 

The decision maintains Musk’s claims that OpenAI’s shift toward a for-profit structure violated early assurances made to him as a co-founder. These claims are directly opposed by OpenAI.

Judge says disputed facts warrant a trial

At a hearing in Oakland, U.S. District Judge Yvonne Gonzalez Rogers stated that there was “plenty of evidence” suggesting that OpenAI leaders had promised that the organization’s original nonprofit structure would be maintained. She ruled that those disputed facts should be evaluated by a jury at a trial in March rather than decided by the court at this stage, as noted in a Reuters report.

Musk helped co-found OpenAI in 2015 but left the organization in 2018. In his lawsuit, he argued that he contributed roughly $38 million, or about 60% of OpenAI’s early funding, based on assurances that the company would remain a nonprofit dedicated to the public benefit. He is seeking unspecified monetary damages tied to what he describes as “ill-gotten gains.”

OpenAI, however, has repeatedly rejected Musk’s allegations. The company has stated that Musk’s claims were baseless and part of a pattern of harassment.

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Rivalries and Microsoft ties

The case unfolds against the backdrop of intensifying competition in generative artificial intelligence. Musk now runs xAI, whose Grok chatbot competes directly with OpenAI’s flagship ChatGPT. OpenAI has argued that Musk is a frustrated commercial rival who is simply attempting to slow down a market leader.

The lawsuit also names Microsoft as a defendant, citing its multibillion-dollar partnerships with OpenAI. Microsoft has urged the court to dismiss the claims against it, arguing there is no evidence it aided or abetted any alleged misconduct. Lawyers for OpenAI have also pushed for the case to be thrown out, claiming that Musk failed to show sufficient factual basis for claims such as fraud and breach of contract.

Judge Gonzalez Rogers, however, declined to end the case at this stage, noting that a jury would also need to consider whether Musk filed the lawsuit within the applicable statute of limitations. Still, the dispute between Elon Musk and OpenAI is now headed for a high-profile jury trial in the coming months.

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