News
SpaceX’s Starship Raptor Vacuum engine plans laid out by CEO Elon Musk
Elon Musk says that SpaceX Starship engine upgrades are on track to begin static fire tests of a Raptor Vacuum variant as few as a “couple months” from now.
Designed to enable more efficient performance in thin atmosphere or vacuum, Musk admitted that the first version(s) of Raptor Vacuum (RVac) will likely be a compromise between efficiency and speed of development. Nevertheless, the faster SpaceX can prepare Raptor Vacuum for flight, the easier it will be for Starship to begin serious (sub)orbital flight tests.
As it turns out, SpaceX’s first and only official render of Raptor – published in September 2016 – showed the engine’s vacuum-optimized variant. In the years since, CEO Elon Musk has vacillated between keeping the vacuum engines as a central Starship feature and simply replacing them with regular sea level Raptors to expedite the spacecraft’s debut. The 2016 and 2017 vehicles featured a mixture of vacuum and sea-level engines, whereas Musk revealed a vehicle with sea-level engines only in 2018.
Perhaps less than a month after Musk’s September 2018 presentation, the SpaceX CEO made the decision to radically redesign the vehicle – newly christened Starship and Super Heavy – by moving from a carbon composite aerostructure to stainless steel. At first, the seven SL Raptors remained a part of the design, but Musk took to Twitter in 2019 to indicate that SpaceX had changed gears again and had reprioritized Raptor Vacuum development.
This came as a bit of surprise and it should go without saying that there’s a significant chance that Musk/SpaceX will oscillate in the opposite direction once again before Raptor Vacuum is actually ready for flight. This time, though, Musk has sketched out a development schedule and strategy that suggests SpaceX is much more serious this time.
Most notably, Musk claims that the first Raptor Vacuum prototype could be ready for static fire testing just a “couple months” from now, an immensely ambitious schedule for any large liquid rocket engine development program. Nevertheless, Musk did indicate that the “V1.0” Raptor Vacuum design would be significantly compromised and “suboptimal”, an intentional decision to prioritize the engine’s “speed of development”.
Even then, Musk believes that the first variant – featuring a shortened bell nozzle – could still be up to 12% more efficient than sea level Raptors and thus already 70-80% of the way to the physical limit of methane-oxygen rocket efficiency.
On a positive note, shrinking V1.0 Raptor Vacuum’s nozzle a bit from its nominal length will likely mean that SpaceX can static fire fully-integrated engines at its McGregor, TX test facilities, critical for speedy development. If not, the company has experience with alternatives through Merlin Vacuum, which can only be tested on the ground with its lengthy nozzle detached. This method just makes it dramatically harder to optimize a vacuum nozzle design, as full-scale, flight-like testing is nearly impossible if a given vacuum engine can’t be tested on the ground with said nozzle installed.
Vacuum engines need such large and unwieldy nozzles in order to make them as efficient as possible. In a very simplistic sense, a rocket engine nozzle directs the flow of superheated, ultrafast gases in order to squeeze as much momentum transfer as possible out of available propellant. The lower the pressure of the surrounding atmosphere is, the more those gases will expand immediately after leaving the nozzle – giant vacuum nozzles simply try to harness the additional momentum available from that extra expansion. This is why rocket exhausts appear to spread and thin out as launch vehicles reach higher and higher altitudes.
In this sense, the perfect theoretical vacuum nozzle is quite literally infinitely long. The job of vacuum rocket engineers is to find the perfect balance between that impractical theoretical perfection and the limits of real-world materials and dynamics. In theory, SpaceX’s sea-level Raptor engines have already been designed to operate in vacuum conditions, while the engine’s closed-cycle design and regeneratively (i.e. propellant) cooled nozzle should apply well to a vacuum design.
If SpaceX is lucky, there will be few roadblocks in the way of simply lengthening a SL Raptor-style nozzle and calling it a day, in which case it would be impressive but not all that surprising if SpaceX is actually able to begin RVac testing before the end of 2019. Once a rough V1.0 engine is in place, the process of optimizing efficiency can be done slowly and methodically, all while exploiting an unprecedented wealth of data from flight and orbit-tested Raptor Vacuum engines.
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Elon Musk
Tesla’s mysterious Robovan makes a sneak peek with Optimus in Terafab video
Elon Musk shared a new Terafab video showing Optimus, Robovans, and a stunningly futuristic campus.
Elon Musk posted a new video of Terafab on X Thursday morning, and the most eye-catching details in it were not the building itself, but two products still awaiting production: Optimus and the Robovan.
The concept render, credited to SpaceX, shows Optimus robots working the grounds of the roughly 2.5-mile-long facility planned for the Gibbons Creek site in Grimes County, while a Robovan glides along an elevated roadway cutting through the building itself, sharing the frame with a Tesla Semi and a Cybercab.
Robovan is the boxy, driverless people and cargo mover Musk unveiled alongside Cybercab at Tesla’s “We, Robot” event in October 2024. He pitched it as a way to move up to 20 passengers at once, or handle freight instead, at a target cost he claimed could fall under a dollar a mile, with no steering wheel or pedals, the same layout as Cybercab. Nearly two years later, Robovan still has no confirmed production timeline and has not shown up in any factory footage, which makes Thursday’s render one of the only recent looks at the vehicle in any form.
Terafab Texas will be the largest and most valuable building on Earth by far.
And it will be stunningly beautiful. pic.twitter.com/4NweOqTL7y
— Elon Musk (@elonmusk) August 6, 2026
Optimus has moved further along. Tesla began converting Fremont’s old Model S and Model X assembly line into a Gen 3 Optimus production line earlier this year, and Musk visited the site on July 1 to mark the changeover. A second, larger Optimus plant is under construction at Giga Texas, targeting volume production in summer 2027 and eventual capacity of 10 million units a year. Tesla AI lead Ashok Elluswamy said this month the robot has “big shoes to fill” in replacing the S and X line, while Musk has repeatedly called Optimus the company’s biggest product of any kind, with a long-term price he has pegged between $20,000 and $30,000.
Check out the “Robovan” from @Tesla
📸: @Teslarati pic.twitter.com/D4es2i9NUe
— TESLARATI (@Teslarati) October 11, 2024
“Terafab Texas will be the largest and most valuable building on Earth by far,” Musk wrote alongside the clip. “And it will be stunningly beautiful.”
One quote post summed up the reaction: “Futuristic scene with RoboVan + Cybercab + Tesla Semi + Optimus.”
Beyond the vehicles, the architecture wrapped around them stands out too. The building’s facade is canted at sharp angles, with illuminated horizontal bands running through what appears to be a multi level interior visible from outside. Below the elevated roadway, pedestrians walk along a plaza next to a reflecting pool, and the skyline behind the campus is dotted with angular spires that read more like sculpture than infrastructure, a departure from the strictly utilitarian look of Gigafactory Texas or Starbase.
The timing tracks with what Terafab representative Riley Trennell told Grimes County residents on Wednesday, when he said renderings of the facility would be released “within days.” Musk’s post followed less than 24 hours later, and Texas Governor Greg Abbott’s office sent out its own release Thursday confirming the project. As Teslarati reported this morning, Terafab’s tax abatement agreements with Grimes County are now signed and active, and SpaceX has sent the county its first $10 million payment under that deal. The dollar figure tied to this phase of construction, per Reuters, is $16.8 billion, one of the first hard capital expenditure numbers attached to Terafab since Musk unveiled the joint Tesla-SpaceX-xAI venture in March.Reaction on X ranged from enthusiastic to skeptical. “God Bless Texas! Everything is bigger and better in Texas!” one reply read. Another was more measured: “Terafab in a decade…..”
Whether the finished building matches the render is a separate question from whether Musk wanted people talking about the render itself. Less than a day after posting, the video had already crossed 5.5 million views.
Cybertruck
Tesla Cybertruck production snaps back after ugly supplier fight
Cybertrucks are piling up again at Giga Texas after Tesla’s court win against a parts supplier.
Cybertruck production at Giga Texas is showing its first visible recovery since Tesla sued a supplier last month over withheld manufacturing tooling.
Aerial observer Joe Tegtmeyer flew over the Austin factory Wednesday morning and counted roughly 100 or more Cybertrucks filling the outbound lot, a sharp jump from the thin numbers seen in recent weeks. The flyover came a day after a judge granted Tesla a temporary restraining order against Angstrom Automotive Group, the parts supplier at the center of the dispute.
Tesla filed an emergency lawsuit in late July after Angstrom told the automaker it planned to close the Troy, Texas facility where Tesla’s die-cast tools, trim dies and other Cybertruck stamping equipment were housed. According to Tesla’s complaint, a shipment of 700 finished parts never left the building, and when Tesla sent representatives to retrieve its equipment, accompanied by law enforcement, they were turned away. Angstrom allegedly then asked for an extra $250,000 a week to keep operating, which Tesla’s filing described as holding its own property for ransom.
TESLA: U.S. District Judge Christopher R. Wolfe of the U.S. District Court for the Western District of Texas, Waco Division granted Tesla a Temporary Restraining Order and Writ of Replevin in its dispute with Angstrom Automotive (Case No. 6:26-cv-00477).
The order authorizes… https://t.co/E1DKcQSxMn pic.twitter.com/LR8aAiV2Og
— S.E. Robinson, Jr. (@SERobinsonJr) August 5, 2026
The restraining order gives Tesla immediate right of entry to Angstrom’s facility to recover the tooling. It is temporary, with a fuller hearing still to come, but the speed of Wednesday’s rebound suggests the Angstrom shortage was indeed the main bottleneck limiting Cybertruck output. Outbound lot counts are an imperfect measure of actual production, since finished trucks can sit for days before shipping, but a lot that full after a lean stretch is a meaningful signal.
Cybertruck output at Giga Texas has fluctuated all year as Tesla worked through supply issues and introduced new trims, including a cheaper Dual Motor AWD version that drew strong early demand.
Elon Musk
Space finally faced the people living next to its next Terafab mega-project
SpaceX confirmed Terafab’s Grimes County site is locked in, with construction starting within months.
SpaceX and Terafab representatives sat across from Grimes County residents for the first time on Wednesday, telling a packed Commissioners Court room that the $55 billion chip manufacturing project is now a done deal at the Gibbons Creek Reservoir site.
The meeting followed a $10 million check SpaceX sent the county earlier this week, satisfying a payment deadline built into the tax abatement agreement both sides signed in June. Elon Musk shared a post on X confirming the payment, and County Judge Joe Fauth told the San Antonio Express-News his office deposited the check after it beat its deadline.
Wednesday’s session, first reported by KBTX, moved the project from paperwork to construction. Terafab representative Riley Trennell told residents the JETI tax break agreements with Iola ISD and Anderson-Shiro CISD are signed and active, and that civil work and foundation prep are starting almost immediately. Renderings of the facility could be released within days, he said, with construction beginning within months.
The foundations for an exciting future are being built in Texas. Next up: Terafab → https://t.co/jGg52Zhn5I pic.twitter.com/SNfSXNr2tb
— SpaceX (@SpaceX) August 6, 2026
Elon Musk launches TERAFAB: The $25B Tesla-SpaceXAI chip factory that will rewire the AI industry
Musk first announced Terafab in March as a joint venture between Tesla, SpaceX and xAI aimed at producing over a terawatt of AI compute annually, an amount that dwarfs the roughly 20 gigawatts the entire global chip industry produces today. Intel joined as a manufacturing partner in April. Musk has said the project needed its own day in the spotlight rather than being squeezed into an earnings call, and for months the Grimes County site remained unconfirmed even as reporting pointed there.
SpaceX attorney Buck Brannon used Wednesday’s meeting to note that the company’s abatement is roughly 78 percent, not the 100 percent some earlier reports suggested. In exchange, SpaceX will pay Grimes County a fixed $20 million a year for 35 years, a total of $710 million, which Brannon said exceeds the $14 million Tesla paid Travis County in 2025.
SpaceX also addressed environmental concerns that have followed the project since Musk’s Terafab partnership with Intel was announced. Representatives said Terafab will not raise electric bills for other ratepayers, will not deplete local water supplies and will not draw down the Navasota River. SpaceX confirmed it owns the Navasota River pumping station, which it plans to use to divert stormwater into the Gibbons Creek Reservoir, and said it will build its own natural gas plants to power the facility rather than pulling from the ERCOT grid.
Grimes County commissioners also approved an addendum letting county employees use ten approved AI chatbots for work, including Grok.
Tesla’s mysterious Robovan makes a sneak peek with Optimus in Terafab video
Tesla Cybertruck production snaps back after ugly supplier fight
