News
SpaceX’s first high-altitude Starship prototype just “passed cryo proof” testing
SpaceX CEO Elon Musk says that the first high-altitude Starship prototype – known as SN8 – just “passed cryo proof” testing in South Texas, potentially setting the ship up for a ~15 km (9.5 mile) flight test in the near future.
Meanwhile, NASA astronaut Bob Hines recently overflew SpaceX’s Boca Chica, Texas Starship factory with several compatriots, offering an excellent aerial view of the company’s bustling facilities in the midst of Starship SN8’s critical cryo proof test campaign.
Hines managed to catch the Moon alongside one of the T-38 trainer jets NASA astronauts routinely use for training and travel, serving as a reminder that SpaceX won $135 million to build a Lunar Starship that might someday return humans to Earth’s lone companion. Likely with or without NASA’s involvement, the Starship prototype production and test program SpaceX is deep in the midst of will directly determine if and when the company visits – and lands on – the Moon and Mars.
Over the last three days, SpaceX has gradually put Starship SN8 – the first prototype meant for high-altitude flight testing – through its paces, beginning with a seemingly aborted “cryo proof” test on October 5/6. During the first attempt, SpaceX appeared to pressurize the rocket tank section with cold nitrogen gas and perhaps a small volume of liquid nitrogen before reopening the highway. Starship SN8 also actuated its large aft flaps under its own power for the first time on October 4th and SpaceX has performed several more actuation tests in the days since.
24 hours later, SpaceX tried again, this time successfully loading Starship SN8’s liquid oxygen and methane propellant tanks with perhaps a thousand metric tons (2.2 million pounds) of liquid nitrogen – used to simulate the ultra-cold temperatures of cryogenic propellant without the risk of a catastrophic fire or explosion. After cryo load, SpaceX reportedly attempted to pressurize the rocket’s tanks to their limits but the test was stopped somewhat short when Starship SN8 sprung “a small leak…near the engine mounts” after reaching pressures of 7 bar (~100 psi).
Precisely as Musk predicted, SpaceX apparently managed to fix the minor leak in less than 24 hours and began the third round of Starship SN8 cryo proof testing late on October 7th. Once again, the rocket was fully loaded with liquid nitrogen and spent some 2-3 hours under cryogenic stress as SpaceX likely stress the thrust structure (“thrust puck”) by simulating the thrust of Raptor engines with hydraulic rams. Nothing out of the ordinary happened and Musk has yet to comment on the test, suggesting that things went largely as planned.
Intriguingly, SpaceX then geared up for a fourth night of cryogenic testing on October 8/9. It’s not entirely surprising that the company would want to test the first Starship built primarily with a new steel alloy as thoroughly as possible. If SN8’s fourth night of testing produces satisfactory results and SpaceX is less than concerned with the leak discovered during the second round of testing, the company could be ready to install three engines and attempt the first multi-Raptor static fire test ever.
Update: SpaceX CEO Elon Musk says that Starship SN8 “passed cryo proof” testing, most likely setting the rocket up for the first triple-Raptor static fire test ever attempted. If SN8 passes static fire testing, it will most likely be outfitted with a nosecone and forward flaps and attempt another three-engine static fire using smaller ‘header’ propellant tanks, ultimately preparing it to support the first high-altitude flight test of a Starship prototype if all goes according to plan.
Check out Teslarati’s Marketplace! We offer Tesla accessories, including for the Tesla Cybertruck and Tesla Model 3.
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:Â
“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.Â
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.Â
“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.Â
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.Â
“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.Â
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
