News
SpaceX repairing heat shield, reinstalling Raptors on first orbital-class Starship
SpaceX has begun reinstalling three of the six Raptor engines that will power the first orbital-class Starship and repairing the heat shield that will hopefully protect it on its first trip to space.
Known as Starship 20 or S20, the 50m (~165 ft) tall steel rocket prototype has been stationed at one of SpaceX’s two suborbital testing pads since August 13th. No testing has been done, though, and a small army of SpaceX technicians and engineers have instead spent the last three or so weeks effectively turning a collection of steel tanks, tubes, and parts into a functional rocket. While it’s unclear why SpaceX chose to do that outfitting work at an unsheltered launch pad, new activity suggests that it may be almost complete.
Exactly one month ago, SpaceX stacked Starship S20 on top of Super Heavy Booster 4 (B4) on August 6th, briefly creating the largest rocket in history and completing a fit test that was admittedly just as much a photo op. Ship 20 was rapidly destacked and returned to SpaceX’s Starbase factory, where all six of its Raptor engines were removed. About a week later, Ship 20 returned to the pad and has remained installed on Suborbital Pad B ever since.
At the time, the implication was that SpaceX had removed Ship 20’s engines to allow the prototype to complete cryogenic proof testing with hydraulic thrust simulators. However, despite having carefully modified Pad B over several weeks for that exact purpose, those modifications were rapidly removed before Ship 20’s second rollout. Precluding a proof test with thrust simulation, the next logical conclusion was that SpaceX would still perform a cryogenic proof test before reinstalling Ship 20’s Raptors and moving on to a static fire campaign.
Now, even that appears to have been p1recluded. Instead, as if Ship 20 were the second or third or fourth in a series of prototypes, SpaceX rolled three center Raptors to Pad B on September 5th and began installing the engines on Starship on the 6th. It’s hard to say anything with confidence given how chaotically Starship S20’s to-be-determined qualification testing has changed in the last several weeks but, with plenty of uncertainty, Raptor installation implies that the vehicle will perform its first ambient pressure and cryogenic proof tests with engines installed.
It remains to be seen if Ship 20’s three vacuum-optimized Raptor engines will also be installed over the next few days (seemingly the logical assumption) or if SpaceX will instead complete proof tests and center Raptor static fire testing before finally moving into new territory. SpaceX has never static fired more than three Raptors at once and certainly never tested multiple Raptor Vacuum (RVac) engines in close proximity – let alone all six simultaneously.
Meanwhile, much of the focus of the last few weeks appears to have been on finishing Ship 20 plumbing and avionics wire runs, though it’s hard to say exactly what has been done. What is extremely visible and easy to follow, though, is the process of finishing the first orbital-class Starship heat shield and repairing a few hundred tiles broken during its pathfinder installation. SpaceX has installed 500-1000+ tiles on flown Starship prototypes like SN15 but the company has never come close to the ~15,000 needed to cover the entire windward side of the world’s largest rocket upper stage.
SpaceX has undertaken that process for the first time over the last six or so weeks and unsurprisingly seen a number of successes and failures. At some point along the way, a significant fraction of the ceramic, dinner-plate-sized tiles SpaceX technicians installed chipped, broke, shattered, or ran into other fitment issues. Over the last month or so, a great deal of progress has been made fixing those problem tiles and SpaceX has also more or less completed tile installation on the angular ‘aerocovers’ that protect Starship’s flap mechanisms – requiring dozens of custom tiles with complex shapes and curves.
As of September 6th, Starship S20’s heat shield appears to be around 95% complete and the installation of Raptor engines implies that the rocket’s plumbing, avionics, and tankage are also nearly finished. In other words, after many weeks of work, SpaceX’s first orbital-class Starship prototype could be ready to kick off cryoproof and static fire testing just a week or so (and maybe less) from now. Stay tuned for updates!
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.
Tesla confirms that it finally solved its 4680 battery’s dry cathode process
Tesla Giga Texas to feature massive Optimus V4 production line
