News
SpaceX Super Heavy booster assembly to start “this week,” says Elon Musk
CEO Elon Musk says that SpaceX is on track to begin fabricating Starship’s first Super Heavy booster prototype later “this week” and even revealed plans to hop that booster in the very near future.
Taller than an entire two-stage Falcon 9 or Falcon Heavy rocket, Super Heavy will be the largest and most powerful liquid rocket booster ever built by a factor of two (or more). Measuring ~70m (~230 ft) tall, Super Heavy will weigh at least 3500 metric tons (7.7 million lb) when fully loaded with liquid oxygen and methane propellant. According to Musk, SpaceX’s thrust target for the booster is 7500 tons (~16.5 million lbf) – significantly more than twice the thrust of the Saturn V and Soviet N-1 rockets and more than three times the thrust of SpaceX’s own Falcon Heavy.
On paper, while multiple times larger and more powerful, Super Heavy will be substantially simpler than Falcon Heavy thanks to its single-core. Built out of the same simple steel rings used to assemble Starship prototypes, Super Heavy should also be substantially cheaper to build than Falcon Heavy. Thanks to the experience SpaceX has already gained through months of Starship production, testing, and iterative improvement, initial Super Heavy prototype production could have a much smoother start, but several major challenges remain.

SpaceX has structured its Starship development program in such a way that the hardest technical challenges are generally first in line. Raptor engine testing came first in September 2016, although SpaceX did simultaneously build and test a full-scale carbon composite liquid oxygen – a material choice that was ultimately made redundant by the move to steel in late 2018. Up next, Starhopper served as a sort of proof of concept for the assembly of a flightworthy steel rocket in an unprotected open-air tent.
Starship Mk1 came next and was built as a full-scale prototype in similarly spartan conditions – but with much thinner steel. Mk1 ultimately failed prematurely, serving as a catalyst for SpaceX to substantially upgrade its South Texas rocket production capabilities, as well as its manufacturing techniques. Beginning in January 2020, SpaceX completed a rapid-fire series of tests with three stout tank prototypes and five full-scale Starship tank sections over the next seven months, passing multiple challenging pressure tests, wet dress rehearsals, Raptor static fires, and even a 150m (500 ft) hop.
The biggest challenges still facing Starship (5+ minute Raptor burns, skydiver-style landings, heat shield qualification, orbital launch/reentry/reuse) are mostly unique to the orbital spacecraft. In other words, with all SpaceX has already accomplished so far with Starship development, it could very well be ready to build a fully-capable Super Heavy prototype right now.
Along those lines, Musk says that there’s a chance that SpaceX will be ready to hop a Super Heavy booster prototype as early as October 2020 – less than two months after the first prototype enters production. Musk also noted that the biggest technical challenge facing Super Heavy is its extraordinarily complex ‘thrust puck’ – a metal structure that must host up to 28 Raptor engines and transfer all of their thrust through the rest of the rocket.
Per past comments, SpaceX will begin booster testing – possibly up to and including the first few orbital launch attempts – with as few Raptor engines as possible. For Musk’s aforementioned booster hop test, Super Heavy could reportedly hop with as few as two Raptors installed. Beyond those early tests and Super Heavy thrust puck development, perhaps only other challenge facing SpaceX is finalizing Raptor’s design to the point that dozens of engines can be built in short order. As of now, SpaceX has completed 40 Raptor prototypes in 18 months, while every Starship/Super Heavy pair will need as many as 34 engines apiece.
Check out Teslarati’s Marketplace! We offer Tesla accessories, including for the Tesla Cybertruck and Tesla Model 3.
Elon Musk
Tesla confirms that work on Dojo 3 has officially resumed
“Now that the AI5 chip design is in good shape, Tesla will restart work on Dojo 3,” Elon Musk wrote in a post on X.
Tesla has restarted work on its Dojo 3 initiative, its in-house AI training supercomputer, now that its AI5 chip design has reached a stable stage.
Tesla CEO Elon Musk confirmed the update in a recent post on X.
Tesla’s Dojo 3 initiative restarted
In a post on X, Musk said that with the AI5 chip design now “in good shape,” Tesla will resume work on Dojo 3. He added that Tesla is hiring engineers interested in working on what he expects will become the highest-volume AI chips in the world.
“Now that the AI5 chip design is in good shape, Tesla will restart work on Dojo3. If you’re interested in working on what will be the highest volume chips in the world, send a note to AI_Chips@Tesla.com with 3 bullet points on the toughest technical problems you’ve solved,” Musk wrote in his post on X.
Musk’s comment followed a series of recent posts outlining Tesla’s broader AI chip roadmap. In another update, he stated that Tesla’s AI4 chip alone would achieve self-driving safety levels well above human drivers, AI5 would make vehicles “almost perfect” while significantly enhancing Optimus, and AI6 would be focused on Optimus and data center applications.
Musk then highlighted that AI7/Dojo 3 will be designed to support space-based AI compute.
Tesla’s AI roadmap
Musk’s latest comments helped resolve some confusion that emerged last year about Project Dojo’s future. At the time, Musk stated on X that Tesla was stepping back from Dojo because it did not make sense to split resources across multiple AI chip architectures.
He suggested that clustering large numbers of Tesla AI5 and AI6 chips for training could effectively serve the same purpose as a dedicated Dojo successor. “In a supercomputer cluster, it would make sense to put many AI5/AI6 chips on a board, whether for inference or training, simply to reduce network cabling complexity & cost by a few orders of magnitude,” Musk wrote at the time.
Musk later reinforced that idea by responding positively to an X post stating that Tesla’s AI6 chip would effectively be the new Dojo. Considering his recent updates on X, however, it appears that Tesla will be using AI7, not AI6, as its dedicated Dojo successor. The CEO did state that Tesla’s AI7, AI8, and AI9 chips will be developed in short, nine-month cycles, so Dojo’s deployment might actually be sooner than expected.
Elon Musk
Elon Musk’s xAI brings 1GW Colossus 2 AI training cluster online
Elon Musk shared his update in a recent post on social media platform X.
xAI has brought its Colossus 2 supercomputer online, making it the first gigawatt-scale AI training cluster in the world, and it’s about to get even bigger in a few months.
Elon Musk shared his update in a recent post on social media platform X.
Colossus 2 goes live
The Colossus 2 supercomputer, together with its predecessor, Colossus 1, are used by xAI to primarily train and refine the company’s Grok large language model. In a post on X, Musk stated that Colossus 2 is already operational, making it the first gigawatt training cluster in the world.
But what’s even more remarkable is that it would be upgraded to 1.5 GW of power in April. Even in its current iteration, however, the Colossus 2 supercomputer already exceeds the peak demand of San Francisco.
Commentary from users of the social media platform highlighted the speed of execution behind the project. Colossus 1 went from site preparation to full operation in 122 days, while Colossus 2 went live by crossing the 1-GW barrier and is targeting a total capacity of roughly 2 GW. This far exceeds the speed of xAI’s primary rivals.
Funding fuels rapid expansion
xAI’s Colossus 2 launch follows xAI’s recently closed, upsized $20 billion Series E funding round, which exceeded its initial $15 billion target. The company said the capital will be used to accelerate infrastructure scaling and AI product development.
The round attracted a broad group of investors, including Valor Equity Partners, Stepstone Group, Fidelity Management & Research Company, Qatar Investment Authority, MGX, and Baron Capital Group. Strategic partners NVIDIA and Cisco also continued their support, helping xAI build what it describes as the world’s largest GPU clusters.
xAI said the funding will accelerate its infrastructure buildout, enable rapid deployment of AI products to billions of users, and support research tied to its mission of understanding the universe. The company noted that its Colossus 1 and 2 systems now represent more than one million H100 GPU equivalents, alongside recent releases including the Grok 4 series, Grok Voice, and Grok Imagine. Training is also already underway for its next flagship model, Grok 5.
Elon Musk
Tesla AI5 chip nears completion, Elon Musk teases 9-month development cadence
The Tesla CEO shared his recent insights in a post on social media platform X.
Tesla’s next-generation AI5 chip is nearly complete, and work on its successor is already underway, as per a recent update from Elon Musk.
The Tesla CEO shared his recent insights in a post on social media platform X.
Musk details AI chip roadmap
In his post, Elon Musk stated that Tesla’s AI5 chip design is “almost done,” while AI6 has already entered early development. Musk added that Tesla plans to continue iterating rapidly, with AI7, AI8, AI9, and future generations targeting a nine-month design cycle.
He also noted that Tesla’s in-house chips could become the highest-volume AI processors in the world. Musk framed his update as a recruiting message, encouraging engineers to join Tesla’s AI and chip development teams.
Tesla community member Herbert Ong highlighted the strategic importance of the timeline, noting that faster chip cycles enable quicker learning, faster iteration, and a compounding advantage in AI and autonomy that becomes increasingly difficult for competitors to close.
AI5 manufacturing takes shape
Musk’s comments align with earlier reporting on AI5’s production plans. In December, it was reported that Samsung is preparing to manufacture Tesla’s AI5 chip, accelerating hiring for experienced engineers to support U.S. production and address complex foundry challenges.
Samsung is one of two suppliers selected for AI5, alongside TSMC. The companies are expected to produce different versions of the AI5 chip, with TSMC reportedly using a 3nm process and Samsung using a 2nm process.
Musk has previously stated that while different foundries translate chip designs into physical silicon in different ways, the goal is for both versions of the Tesla AI5 chip to operate identically. AI5 will succeed Tesla’s current AI4 hardware, formerly known as Hardware 4, and is expected to support the company’s Full Self-Driving system as well as other AI-driven efforts, including Optimus.