News
SpaceX finishes stacking new Starship for the first time in six months
For the first time in more than half a year, SpaceX has stacked a new Starship prototype to its full height, hopefully marking the end of a period of relatively slow progress.
That period began when Starship S20 was stacked to its full height in early August 2021. Until very recently, Ship 20 was said and expected to be the prototype assigned to Starship’s first orbital test flight, making it exceptionally important. In an unusual change in attitude, SpaceX may have felt the same, which may explain why Starship S20’s first static fire test took place more than two months after it first left the factory. A year prior, Starships SN9, SN10, SN11, and SN15 all completed proof testing a matter of weeks after rollout.
That sudden change of pace relative to past development has meant that Ship 20 is the only Starship prototype SpaceX has tested since May 2021 and the only Starship to graduate from final assembly to testing in the last six months. In that period, Ship 20 has completed a few major cryogenic proof tests and four static fires – two of which ignited all six Raptor engines. While Ship 20’s six-engine tests were unprecedented and marked a major program milestone, SpaceX once static-fired Starship SN9 three times in one day in January 2021.
However, that period of sluggish prototype testing may finally be coming to an end. In August 2021, when SpaceX stacked Starship S20 and Super Heavy B4 for the first time, the general assumption was that the seemingly imminent march towards orbital flight testing would be similar to SpaceX’s attempts to land a Starship from medium altitude between December 2020 and May 2021 – lots of prototypes in flow and multiple back-to-back tests and launches, in other words. That was not the case.
Starship S21, for example, began final assembly in mid-October 2021 and its tank section and nose section were both fully stacked less than a month later. However, rather than stack them into a second complete ship, SpaceX has left those separate assemblies sitting around Starbase for the last three months. Simultaneously, while Ship 21’s apparent limbo seemed to imply that SpaceX was implementing another block upgrade and moving on to newer prototypes, the company actually started stacking Starship S22 about a week after S21’s separate sections were completed. Only three months later have SpaceX’s plans for those three sections finally become clear.
On February 14th, 2022, Ship 22’s tank section followed Ship 21’s nose section into Starbase’s high bay assembly facility, where they were quickly stacked to form a full Starship prototype the same day. This raises the question: why?



Given that Starship S20 effectively completed qualification testing with three successful static fires in December 2021 and a fourth in early January 2022 and has been seemingly ready to fly ever since, its Super Heavy booster readiness – not ship readiness – that appears to be holding SpaceX back. Perhaps because of pad readiness issues, SpaceX has yet to perform a single Super Heavy static fire test – or even a less risky wet dress rehearsal – at the orbital launch site. As such, it’s hard to say why SpaceX has suddenly decided to finish Ship 22 instead of focusing on a newer version of Starship (S24) and Super Heavy (B7) – both of which are expected to debut upgrades.
It’s possible that Ship 22 is being completed merely as practice for the Starbase workforce, who have gone half a year without fully assembling another ship prototype, but then there would have been no reason not to install Ship 21’s nose on Ship 21’s tank section instead of withholding it for Ship 22. Ship 22 could also be a replacement for Ship 21 if appearances are misleading and SpaceX uncovered issues with the older prototype during testing but again, no booster is ready to launch either ship.
Regardless of the outcome or purpose of Ship 22, seeing any new Starship prototype completed is an exciting and interesting change of pace after half a year of following the windy paths of Ship 20, Booster 5, and Ship 21 to their uncertain goals.
News
Tesla confirms that it finally solved its 4680 battery’s dry cathode process
The suggests the company has finally resolved one of the most challenging aspects of its next-generation battery cells.
Tesla has confirmed that it is now producing both the anode and cathode of its 4680 battery cells using a dry-electrode process, marking a key breakthrough in a technology the company has been working to industrialize for years.
The update, disclosed in Tesla’s Q4 and FY 2025 update letter, suggests the company has finally resolved one of the most challenging aspects of its next-generation battery cells.
Dry cathode 4680 cells
In its Q4 and FY 2025 update letter, Tesla stated that it is now producing 4680 cells whose anode and cathode were produced during the dry electrode process. The confirmation addresses long-standing questions around whether Tesla could bring its dry cathode process into sustained production.
The disclosure was highlighted on X by Bonne Eggleston, Tesla’s Vice President of 4680 batteries, who wrote that “both electrodes use our dry process.”
Tesla first introduced the dry-electrode concept during its Battery Day presentation in 2020, pitching it as a way to simplify production, reduce factory footprint, lower costs, and improve energy density. While Tesla has been producing 4680 cells for some time, the company had previously relied on more conventional approaches for parts of the process, leading to questions about whether a full dry-electrode process could even be achieved.
4680 packs for Model Y
Tesla also revealed in its Q4 and FY 2025 Update Letter that it has begun producing battery packs for certain Model Y vehicles using its in-house 4680 cells. As per Tesla:
“We have begun to produce battery packs for certain Model Ys with our 4680 cells, unlocking an additional vector of supply to help navigate increasingly complex supply chain challenges caused by trade barriers and tariff risks.”
The timing is notable. With Tesla preparing to wind down Model S and Model X production, the Model Y and Model 3 are expected to account for an even larger share of the company’s vehicle output. Ensuring that the Model Y can be equipped with domestically produced 4680 battery packs gives Tesla greater flexibility to maintain production volumes in the United States, even as global battery supply chains face increasing complexity.
Elon Musk
Tesla Giga Texas to feature massive Optimus V4 production line
This suggests that while the first Optimus line will be set up in the Fremont Factory, the real ramp of Optimus’ production will happen in Giga Texas.
Tesla will build Optimus 4 in Giga Texas, and its production line will be massive. This was, at least, as per recent comments by CEO Elon Musk on social media platform X.
Optimus 4 production
In response to a post on X which expressed surprise that Optimus will be produced in California, Musk stated that “Optimus 4 will be built in Texas at much higher volume.” This suggests that while the first Optimus line will be set up in the Fremont Factory, and while the line itself will be capable of producing 1 million humanoid robots per year, the real ramp of Optimus’ production will happen in Giga Texas.
This was not the first time that Elon Musk shared his plans for Optimus’ production at Gigafactory Texas. During the 2025 Annual Shareholder Meeting, he stated that Giga Texas’ Optimus line will produce 10 million units of the humanoid robot per year. He did not, however, state at the time that Giga Texas would produce Optimus V4.
“So we’re going to launch on the fastest production ramp of any product of any large complex manufactured product ever, starting with building a one-million-unit production line in Fremont. And that’s Line one. And then a ten million unit per year production line here,” Musk stated.
How big Optimus could become
During Tesla’s Q4 and FY 2025 earnings call, Musk offered additional context on the potential of Optimus. While he stated that the ramp of Optimus’ production will be deliberate at first, the humanoid robot itself will have the potential to change the world.
“Optimus really will be a general-purpose robot that can learn by observing human behavior. You can demonstrate a task or verbally describe a task or show it a task. Even show it a video, it will be able to do that task. It’s going to be a very capable robot. I think long-term Optimus will have a very significant impact on the US GDP.
“It will actually move the needle on US GDP significantly. In conclusion, there are still many who doubt our ambitions for creating amazing abundance. We are confident it can be done, and we are making the right moves technologically to ensure that it does. Tesla, Inc. has never been a company to shy away from solving the hardest problems,” Musk stated.
Elon Musk
Rumored SpaceX-xAI merger gets apparent confirmation from Elon Musk
The comment follows reports that the rocket maker is weighing a transaction that could further consolidate Musk’s space and AI ventures.
Elon Musk appeared to confirm reports that SpaceX is exploring a potential merger with artificial intelligence startup xAI by responding positively to a post about the reported transaction on X.
Musk’s comment follows reports that the rocket maker is weighing a transaction that could further consolidate his space and AI ventures.
SpaceX xAI merger
As per a recent Reuters report, SpaceX has held discussions about merging with xAI, with the proposed structure potentially involving an exchange of xAI shares for SpaceX stock. The value, structure, and timing of any deal have not been finalized, and no agreement has been signed.
Musk appeared to acknowledge the report in a brief reply on X, responding “Yeah” to a post that described SpaceX as a future “Dyson Swarm company.” The comment references a Dyson Swarm, a sci-fi megastructure concept that consists of a massive network of satellites or structures that orbit a celestial body to harness its energy.
Reuters noted that two entities were formed in Nevada on January 21 to facilitate a potential transaction for the possible SpaceX-xAI merger. The discussions remain ongoing, and a transaction is not yet guaranteed, however.
AI and space infrastructure
A potential merger with xAI would align with Musk’s stated strategy of integrating artificial intelligence development with space-based systems. Musk has previously said that space-based infrastructure could support large-scale computing by leveraging continuous solar energy, an approach he has framed as economically scalable over time.
xAI already has operational ties to Musk’s other companies. The startup develops Grok, a large language model that holds a U.S. Department of Defense contract valued at up to $200 million. AI also plays a central role in SpaceX’s Starlink and Starshield satellite programs, which rely on automation and machine learning for network management and national security applications.
Musk has previously consolidated his businesses through share-based transactions, including Tesla’s acquisition of SolarCity in 2016 and xAI’s acquisition of X last year. Bloomberg has also claimed that Musk is considering a merger between SpaceX and Tesla in the future.