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
Elon Musk’s surprise addition to the X Takeover lineup has fans talking
Elon Musk will join Saturday’s X Takeover at Giga Texas for a live virtual interview.
Elon Musk will join X Takeover at Giga Texas on Saturday for a live virtual interview, according to Sawyer Merritt, who shared the news late Thursday. Musk will not be on stage in Austin. The conversation is set to stream for free on the @teslaownersSV account on X.
Organizers had kept expectations in check. In a September update, Tesla Owners Silicon Valley said Musk had appeared at the event twice before but was not promising a third appearance, even as fans hoped he would walk the Giga Texas grounds in person. A virtual spot matches 2024, when Musk gave a surprise interview of about an hour to the crowd in San Luis Obispo, as Teslarati reported at the time.
Wasn’t expecting this 🫡
— Tesla Owners Silicon Valley (@teslaownersSV) October 9, 2026
This year’s edition is a first in several ways. It is the first X Takeover held outside California and the first at a Tesla facility, with tickets selling out in eight days. Tesla provides the venue, but the event is produced independently by Tesla Owners Silicon Valley. The main event runs from 10 a.m. to 6 p.m. CT, followed by a drone and light show at 9 p.m. Maye Musk is the keynote speaker, Franz von Holzhausen is set for a virtual keynote, and Nicki Minaj is the special guest. Joe Tegtmeyer, whose drone footage Teslarati used to track the Optimus factory steel frame at Giga Texas, is also on the speaker list.
Musk’s interview topics have not been revealed, but the backdrop is busy. Tesla doubled its Cybercab fleet in Austin in late September, and last week Musk explained why Robotaxi hours only moved from 10 p.m. to 11 p.m.. Merritt also reported Thursday that Texas DMV records now show 319 registered Cybercabs, up from 169. NHTSA’s deadline for Tesla’s sworn answers on Cybercab certification is October 30, and Tesla reports third quarter earnings on October 21.
Fans who cannot make it to Austin can watch the livestream on X. Musk tends to say more in unscripted settings than he does in prepared remarks, which is the reason this one is worth having open on Saturday.
News
It’s official: SpaceX takes aim at Verizon, AT&T, and T-Mobile
SpaceX is buying 800 MHz spectrum from Grain to turn Starlink Mobile into a carrier.
SpaceX has agreed to buy a nationwide block of low band wireless spectrum, a deal the company says will let Starlink Mobile operate as a full US carrier rather than a satellite add-on for someone else’s network.
The company announced the agreement on X on Thursday afternoon, saying it will “pave the way for @Starlink to become a major mobile carrier in the US.” The seller is Grain Management, a private investment firm that confirmed in a statement that SpaceX will acquire 100% of its nationwide 800 MHz portfolio. That covers up to 14 MHz of paired spectrum in the 817 to 824 MHz and 862 to 869 MHz bands. Neither side disclosed a price, and the deal still needs FCC approval.
We announced an agreement to acquire a nationwide low-band spectrum license portfolio that will pave the way for @Starlink to become a major mobile carrier in the US.
With this new spectrum and our Gen2 constellation, Starlink Mobile can ensure Americans have access to high-speed mobile broadband no matter where they are → https://t.co/1Uaf48v5pm
— SpaceX (@SpaceX) October 8, 2026
Grain only recently picked up the licenses itself. It bought the portfolio from T-Mobile in a transaction that closed in August, paying cash plus its own 600 MHz spectrum. Rival AST SpaceMobile had been testing satellites on the same bands before SpaceX stepped in.
SpaceX said its 2 GHz spectrum will handle high bandwidth capacity, while the new 800 MHz layer “ensures Starlink Mobile’s signal penetrates through obstacles, such as walls, and can provide service to customers’ devices even when they are in buildings.” The company added that most existing phones already support the band, so customers would not need new hardware to use it.
That 2 GHz spectrum came from SpaceX’s EchoStar acquisition last year, which gave the company exclusive S band rights in the US and global Mobile Satellite Service licenses. The Grain spectrum is different in an important way: it is tailored for service from ground towers, not satellites. SpaceX said that combination would make Starlink Mobile “the first network operator to deploy both satellite and terrestrial spectrum.”
The announcement also follows a key regulatory win. Earlier this week, the FCC approved SpaceX’s plan to deploy 15,000 second generation Starlink Mobile satellites, which the company has said will carry up to 100 times the data density of the current system, as Teslarati previously reported.
Shares of AT&T, Verizon and T-Mobile fell in extended trading after the announcement. T-Mobile is currently SpaceX’s launch partner for Starlink Mobile in the US, which makes its position the most complicated of the three.
SpaceX has not been subtle about its plans. During the company’s August earnings call, President and COO Gwynne Shotwell said she expected Starlink Mobile to win over customers from the major carriers. “I anticipate us to be able to acquire quite a few of their customers because I think our service will be better,” she said, pointing to dead zone coverage and resilience during disasters. Shotwell also described plans for low cost cellular base stations that could pair with existing Starlink dishes.
SpaceX has targeted 2027 for deployment of its next generation Starlink Mobile satellites, with upgraded service expected by the end of that year. The FCC review of the Grain deal now determines when the terrestrial half of that network can come online.
Elon Musk
Trump presents Elon Musk with National Medal of Science, calls him “modern-day Thomas Edison”
Trump gave Elon Musk the National Medal of Science and compared him to Thomas Edison.
Elon Musk now has the highest honor the U.S. government gives to scientists and engineers. President Donald Trump presented him with the National Medal of Science on Thursday at the White House’s “Science: A New Golden Age” summit, held at the Institute of Peace in Washington, according to the White House.
Trump called Musk a “national treasure” and “our modern-day Thomas Edison.” “Few Americans in history have done more to advance America’s national interest than Elon in one field after another,” the president said. He also described Musk as an “industrial titan, brilliant engineer and one of the greatest technology founders to ever live.”
The official citation credits Musk “for engineering achievements of extraordinary ambition and scale that have pushed the frontiers of space exploration, intelligent systems, communications, and beyond, renewing American technological leadership and opening a new chapter in American manufacturing.” Tesla is not named in it, but “intelligent systems” and “American manufacturing” cover a lot of ground that Tesla and the Terafab chip project occupy.
Google co-founder Sergey Brin, Nvidia CEO Jensen Huang and AMD CEO Lisa Su received the same medal. Microsoft CEO Satya Nadella and Dell Technologies CEO Michael Dell were given the National Medal of Technology and Innovation. It was the first time Trump has handed out either award in his two terms. As Teslarati noted when the list was first reported on Wednesday, the National Science Foundation says 529 people have received the Medal of Science since Congress created it in 1959.
🚨 IT’S OFFICIAL: President Trump just PERSONALLY presented Elon Musk the National Medal of Science for his INCREDIBLE contributions to our nation
I can’t think of ANYONE who deserves this honor more 👏🏻
Congratulations, @elonmusk! https://t.co/GkAaVp9wb9
— Nick Sortor (@nicksortor) October 8, 2026
The ceremony closes a loop that opened in 2025, when Musk left DOGE and criticized the “Big Beautiful Bill,” sparking a public feud. Al Jazeera noted that Musk was the largest contributor to Trump’s 2024 campaign, and CNBC reported that all of the honorees have given financially to Trump or Republican causes in some form. The reconciliation has moved quickly in recent weeks. Musk sat at Trump’s left at the September 29 White House AI lunch, was named to help lead the Pentagon’s Project Meridian study on the future of warfare, and adopted the administration’s “super intelligence” wording when he said SpaceXAI will become SpaceXSI.
For Tesla and SpaceX shareholders, the practical question is what the closer relationship means for federal approvals. Tesla’s Robotaxi and Cybercab expansion depends on national autonomy rules, and SpaceX’s Starship and Starlink plans run through the FAA, FCC and NASA. Thursday’s ceremony did not change any of that directly.
Elon Musk’s surprise addition to the X Takeover lineup has fans talking
It’s official: SpaceX takes aim at Verizon, AT&T, and T-Mobile
Trump presents Elon Musk with National Medal of Science, calls him “modern-day Thomas Edison”
The Pentagon taps Elon Musk to design the battlefield of the future
Tesla Roadster’s new patent preps white-knuckle speeds, keeping it grounded
