SpaceX
SpaceX’s Starship hopper spotted with trio of dual-bell Raptor engines
Following a brief ‘hop’ (via crane) off of a concrete build stand, the aft section of SpaceX’s first full-scale Starship hopper (Starhopper?) revealed that SpaceX technicians have already installed what appear to be three real Raptor engines, presumably the first time the propulsion system has ever been mounted to something that might eventually fly.
For a number of reasons, there is a strong chance that these Raptors are actually just boilerplate placeholders standing in as structural guides for the real deal some months down the line. On the other hand, there are also a number of reasons to assume that these apparent engines are indeed real Raptors.
Star ship hopper might be a bit bigger than we thought and with the crane placements over the nose end of the vehicle. This could suggest, @SpaceX are planning to move the segment elsewhere perhaps to the welding stand? We will have to wait and see. (Austin Barnard📸) #2019🚀 pic.twitter.com/kn8hhUPWCU
— Austin Barnard🚀 (@austinbarnard45) January 1, 2019
Despite an already shocking series of rapid-fire developments in the South Texas Starhopper saga, the abrupt appearance of what appears to be three Raptor engines – mirroring CEO Elon Musk’s recent statement that the test vehicle would sport three Raptors – is by far the most unexpected moment yet for the prototype Starship. Purportedly a full-scale prototype of BFR’s upper stage/spaceship (now known as Starship), Musk indicated over the last two weeks that the hopper has been designed to perform a number of hop tests in which the craft’s three Raptors would power it to a range of (relatively low) altitudes above Boca Chica, Texas.
According to a recent FCC filing related to this test program, SpaceX is currently seeking a license for Starship hop tests that will not exceed 5 km (3.1 mi) in altitude and/or 6 minutes in duration. There is admittedly nothing mentioned about the maximum allowed velocity during those tests, but – much like Blue Origin performs supersonic tests of New Shepard in Cape Horn, Texas – SpaceX will likely seek and be granted permission to break the sound barrier during those hypothetical tests. Nevertheless, a 5km ceiling is a fairly significant cap on the range of performance Starhopper will be able to test – accelerating vertically at 2Gs, Starhopper could travel from sea level to 5km in less than 30 seconds while reaching speeds no higher than Mach 1-1.5.
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- SpaceX technicians and engineers are continuing to work at a breakneck pace on Starhopper. (NASASpaceflight – bocachicagal)
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- At this rate, the hopper will likely wind up around 40m (130 feet) tall. (NASASpaceflight – bocachicagal)
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- A close examination of these three engine-like protrusions suggests a level of fit and finish far exceeding a boilerplate stand-in. (NASASpaceflight – bocachicagal)
Combined with the apparent fact that this Starhopper’s fins seem unlikely to ever actuate (i.e. no aerodynamic control surfaces), it’s probable that this ad hoc prototype is only meant to perform a very limited range of hop tests, perhaps as basic as ironing out the kinks of operating a trio of gimballed Raptors and ensuring that they can safely and reliably launch, hover, and land a very large Starship-shaped mass simulator. Falcon 9’s Grasshopper and F9R reusability testbeds performed a very similar task some five years ago, offering SpaceX engineers the opportunity to optimize software and hardware needed to reliably recover real orbital-class rockets after launch. Although Falcon 9 has nine gimballed Merlin 1D engines, SpaceX has long sided with the sole center Merlin as the dedicated landing engine and has only briefly experimented with triple-Merlin landing burns.
Dual-expansion whaaaaat?
According to Musk, Raptor – an advanced liquid methane and oxygen engine with a uniquely efficient propulsion cycle – was expected to produce an impressive ~2000 kN (200 ton, 450K lbf) of thrust in its finished form as of September 2018. However, Musk also mentioned in a late-2017 Reddit AMA that SpaceX engineers were modifying the ship’s design to ensure engine-out reliability during all regimes of flight, landing in particular. To accomplish this feat with an engine as powerful as Raptor, two or three Raptors – capable of producing as much as 600 tons of thrust total – would need to reliably throttle as low as 25%, assuming a landing mass of around 150t. To allow a nearly empty ship (~100t) to still reliably land with three Raptors ignited, the engines would need to be able to throttle to 20% or less.
Known as deep throttling in rocketry, ensuring stable combustion and thrust at 20% (let alone 40%) throttle is an extraordinarily challenging feat, often subjecting engines to forces that can literally tear non-optimized hardware apart. To achieve such a deep throttle capability without excessively disrupting the engine’s design, SpaceX appears to have potentially sided with less efficient but extremely simple alternative, known as a dual-bell (or dual-expansion) rocket nozzle. A 1999 Rocketdyne paper concisely explained the primary draws of such a nozzle:
“The [altitude-compensating] dual-bell nozzle offers a unique combination of performance, simplicity, low weight, and ease of cooling” – Horn & Fisher, 1999
Exactly
— Elon Musk (@elonmusk) December 27, 2018
Given that SpaceX has decided to delay the introduction and certification of a vacuum-optimized Raptor engine, choosing to instead use the same Raptor on both BFR stages, something like a dual-bell nozzle would be one of the best possible ways for the company to retain some of the efficiency benefits of a vacuum engine while also drastically improving design simplicity, ease of manufacturing, and cutting development time. Aside from offering efficiency gains by way of altitude compensation, a dual-bell nozzle also happens to enable a given engine to operate a much wider throttle range by mitigating problems with flow separation and instability.
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- A gif of Raptor throttling over the course of a 90+ second static-fire test in McGregor, Texas. (SpaceX)
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- Note that Merlin 1D and prior Raptor prototypes both feature traditional single nozzles. (Pauline Acalin)
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- An overview of dual-bell and deflection nozzles. Raptor appears to have now graduated to the former style. (Johan Steelant, 2011)
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- Starhopper’s Raptors feature a very distinct seam and second curve, indicative of a dual-bell nozzle. (NASASpaceflight /u/bocachicagal)
For Starhopper and Starship, both aspects are an undeniable net-gain and it’s entirely possible that these dual-bell nozzles – if successfully demonstrated – could find their way onto Falcon 9 and Falcon Heavy to further boost their booster performance and efficiency.
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SpaceX just locked up a NASA record no other U.S. spacecraft can touch
SpaceX’s Crew-13 Dragon reached the ISS in under eight hours, and NASA confirmed a record.
SpaceX now owns every spot on the list of the five fastest trips a U.S. spacecraft has ever made to the International Space Station, and its newest entry beat the old mark by more than four hours.
Crew Dragon Grace docked to the forward port of the station’s Harmony module at 7:05 p.m. ET on October 1, just 7 hours and 55 minutes after lifting off from Space Launch Complex 40 at Cape Canaveral. NASA confirmed the milestone in a space station blog update, writing that the flight “marked the fastest launch‑to‑docking of a U.S. spacecraft in the history of the International Space Station.”
The previous U.S. record also belonged to Dragon. SpaceX’s uncrewed CRS-31 cargo mission reached the station in a little over 12 hours in November 2024. The fastest crewed trip before last week was Crew-11, which took 14 hours and 43 minutes in August 2025, according to Space.com.
A post that Elon Musk reposted on Monday filled out the rest of the ranking. Behind Crew-13, CRS-31 and Crew-11 sit Axiom’s Ax-2 mission at 15 hours and 35 minutes and NASA’s Crew-4 at 15 hours and 44 minutes. All five flew on Dragon.
SpaceX turned a heralding moment for Starship into its greatest
Crew-13 carried NASA astronauts Jessica Watkins and Luke Delaney, Canadian Space Agency astronaut Joshua Kutryk, and Roscosmos cosmonaut Sergey Teteryatnikov. NASA had projected a docking around 8 p.m. ET, as Teslarati reported the day before launch, and Dragon arrived nearly an hour early. Our launch day coverage noted that the flight was lined up to be the quickest Crew Dragon transit yet.
The speed came from timing more than hardware. SpaceX’s Julianna Scheiman said the station “was in an opportune spot in space,” which let Dragon start closing the gap almost immediately after reaching orbit. “This is close to the fastest it could be,” she added. Most Crew Dragon flights still take close to a day, using a series of Draco thruster burns to raise and phase their orbit before arrival.
Dragon’s next job at the station is a departure. NASA said Monday it is targeting 8:05 a.m. ET on Wednesday, October 7, for Crew-12 to undock, setting up a splashdown off the coast of California around 11:34 a.m. on Thursday. Clearing that port makes room for CRS-35, a cargo Dragon carrying the final set of iROSA solar arrays.
Dragon remains NASA’s only operational ride to the station while Boeing’s Starliner stays grounded, and the agency recently added Crew-15, Crew-16 and Crew-17 to SpaceX’s contract in a $946 million modification.
Elon Musk has acknowledged that early discussions with Taiwan Semiconductor Manufacturing Company (TSMC) could bring the company into his ambitious Terafab semiconductor project, signaling a possible partnership with the world’s leading contract chipmaker.
Musk confirmed that early talks are underway, but as of right now, they are “just discussions.” There is no confirmation of a deal nor dismissal of the possibility of one, leaving open the prospect of one of the largest advanced-chip collaborations under discussion in the U.S.
@wholemars Just discussions, but something may come of it
— Elon Musk (@elonmusk) October 3, 2026
The report that speculated on potential discussions between Terafab and TSMC comes from Tim Culpan, who outlined a few ways the collaboration could operate. One is TSMC using the project as an “anchor customer” for future facilities in Texas, potentially contributing process expertise, operational know-how, or capacity while Terafab provides capital, long-term purchase commitments, or both.
Tesla and SpaceX jointly developed the Terafab project, with Intel already participating on the tech side. Elon Musk announced the project in March, and it intends to produce more than one terawatt of AI compute capacity annually once fully built.
Company statements place the first phase at approximately $16.8 billion in cost, with later filings pointing to a total that could reach well into the tens of billions across multiple stages.
Intel joined the effort in April 2026 and is expected to supply its 14A manufacturing process for the full-scale plant.
Musk has said existing suppliers, including Samsung and TSMC, remain important for near-term needs; Tesla already has production arrangements with Samsung for AI5 and AI6 chips, but that future demand from Optimus robots, Cybercab vehicles, and planned space-based data centers will eventually exceed what the global industry can currently deliver.
Terafab is positioned as the long-term answer to that projected shortfall, and Tesla did something similar during COVID to avoid a chip shortage. This is just a much larger-scale solution.
If the partnership were to materialize, it would add TSMC’s industry-leading strategies to a project that already combines Tesla’s and SpaceX’s capital and offtake with Intel’s process technology. For now, the only public confirmation is Musk’s brief acknowledgement that conversations are occurring.
Elon Musk
Elon Musk follows Trump’s lead, says a SpaceX name change is coming
Elon Musk says SpaceXAI will become SpaceXSI, marking its second rebrand in under three months.
Elon Musk wants to rename his artificial intelligence company again, less than three months after its last rebrand.
In a string of posts on X early Sunday morning, Musk wrote “No more AI,” followed by “SI” and “It’s better.” He then added, “SpaceX is a super intelligence company.” When a user asked whether SpaceXAI could become SpaceXSI, Musk replied, “Yes, we will make that change.”
The posts extend a terminology push that began at the White House last week. On September 29, President Donald Trump signed an executive order directing federal agencies to replace “artificial intelligence” and “AI” with “Super Intelligence” and “SI” on government websites, policy documents and press releases. The same day, Musk sat beside Trump as the heads of the largest AI companies signed a voluntary safety accord, as Teslarati reported. Speaking to reporters afterward, Musk caught himself mid sentence: “I think it is worth highlighting the positive benefits of A.I. … S.I., pardon me.”
Elon Musk and Trump are closer than ever, and Tesla could be the big winner
SpaceXSI would be the third name for the business since February. SpaceX acquired xAI on February 2 in a deal that valued the combined company at $1.25 trillion. In May, Musk said xAI would be dissolved as a separate company, and on July 6 the division adopted the SpaceXAI name and a new logo that placed the xAI letters inside the SpaceX identity.
Musk gave no timeline. He did not say whether SpaceXSI would be a legal name change or a branding update, whether the @SpaceXAI handle on X would change, or how the shift would apply to products like Grok. The company had not issued a formal announcement as of Sunday morning.
The change would reach well beyond a chatbot. SpaceXAI now houses Grok, the X platform, the Colossus training clusters in Memphis and the coding tool Cursor, which SpaceX acquired in August. It also runs the orbital compute effort SpaceX is building around Nvidia hardware, which Musk said during the company’s first earnings call would be exclusive to Nvidia.
It’s unclear if rivals like Anthropic, OpenAI, Google, Meta and Nvidia have plans to also rename their companies or products. OpenAI CEO Sam Altman has continued to say “AI” in public, while Nvidia CEO Jensen Huang has gone partway, describing data centers as “super intelligence factories.”
The rename would also line up SpaceX’s AI branding with the federal government’s language as Musk takes on a new advisory role at the Pentagon, where he is helping lead the Project Meridian study on the future of warfare.
SpaceX just locked up a NASA record no other U.S. spacecraft can touch
Elon Musk teases TSMC as potential Terafab partner
