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.
Check out Teslarati’s Marketplace! We offer Tesla accessories, including for the Tesla Cybertruck and Tesla Model 3.
SpaceX has achieved an incredible milestone by launching its 11,000th Starlink satellite into orbit.
This accomplishment occurred during the Starlink Group 17-50 mission, which lifted off on August 19 at 04:01 UTC from Space Launch Complex 4 East at Vandenberg Space Force Base in California.
Falcon 9 launches 24 @Starlink satellites from California pic.twitter.com/UscpmAxDls
— SpaceX (@SpaceX) August 19, 2026
A Falcon 9 rocket carried 24 Starlink V2 Mini satellites on this flight, successfully deploying them into low Earth orbit approximately one hour after liftoff. The first stage booster, identified as B1097 on its twelfth flight, landed successfully on the droneship Of Course I Still Love You in the Pacific Ocean.
According to tracking data compiled around that date, this deployment brought the total number of Starlink satellites in orbit to just over 11,000.
The Starlink program began with test satellites known as Tintin A and B, launched on February 22, 2018. The first operational batch of 60 Starlink satellites followed on May 24, 2019, when a Falcon 9 rocket lifted off from Cape Canaveral. Those initial satellites marked the start of a rapid expansion that has continued for more than seven years.
SpaceX has conducted hundreds of dedicated Starlink missions since then, routinely launching batches of 20 to 30 satellites at a time using reusable Falcon 9 rockets. By mid-2026, the company had already surpassed 12,000 total satellites launched across all versions, with continuous replacements for units that deorbit as designed to manage space debris.
Looking ahead, SpaceX continues to expand the Starlink constellation to enhance global broadband coverage, capacity, and speed. The network already serves millions of users across more than 160 countries and supports applications ranging from residential internet to maritime, aviation, and emergency services.
Future plans center on next-generation hardware, including larger V3 satellites capable of delivering substantially higher throughput, which require the increased payload capacity of the Starship vehicle currently under development and testing.
In July, SpaceX submitted an application to the Federal Communications Commission seeking authority for a Gen3 constellation of up to 100,000 satellites. These spacecraft would operate in very low Earth orbit shells at altitudes near 325 kilometers and 475 kilometers. The filing requests use of existing Ku, Ka, V, and E band spectrum along with new greenfield W and D band frequencies between 92 and 275 GHz.
SpaceX states that the expanded system aims to deliver multi-gigabit symmetrical broadband to consumers, enterprises, governments, and billions of AI-powered devices worldwide while handling a majority of global internet traffic. Approval and subsequent deployment would depend on regulatory review and the operational readiness of Starship for high-volume launches.
This ambitious scale reflects SpaceX’s ongoing commitment to providing ubiquitous high-speed connectivity from space.
Tesla has opened a new sweepstakes to allow the public to be among the first to take an initial ride in a Cybercab. This all-electric, steering-wheel-less, pedal-less vehicle is the centerpiece of the company’s autonomous ride-hailing platform, Robotaxi.
There are two ways Tesla fans can get to Austin to take part in the first public rides of the Cybercab: by riding on the Robotaxi platform by August 23, or by mailing a very specific entry to their Headquarters at Gigafactory Texas.
Tesla announced the latter portion of the sweepstakes last night:
🚨 Want to win a trip to Austin to ride in one of the first Cybercab rides ever?
Here’s how:
Tesla has opened up a new sweepstakes to ride in a Cybercab upon its public launch. Here’s the details.
There are two methods of entry into the sweepstakes, and they are as follows:… pic.twitter.com/iJRd4evuWo
— TESLARATI (@Teslarati) August 19, 2026
Tesla will give one entry into the sweepstakes if you mail a 3″ by 5″ piece of paper with your full name, mailing address, telephone number, email address, and date of birth to their address:
Tesla, Robotaxi Sweeps Event
1 Tesla Road,
Austin, TX 78725
There is a limit of one entry per stamped envelope. You can send as many as you’d like, but they must be in separate envelopes.
The company’s unique strategy to give people the opportunity to ride in a Cybercab before pretty much anyone else outside of the company is a hilarious but spot-on representation of how Tesla operates. In classic fashion, they had the perfect response to the event:
— Tesla (@Tesla) August 19, 2026
Cybercab will launch later this month, it appears, especially as it plans to announce the winners of the sweepstakes on August 25. The car has already been operating internally, as employees have been able to utilize the Cybercab for rides in some capacity, something it announced earlier this month.
Tesla weirdly confirms Cybercab employee rides, a huge milestone
Moving forward, the big goal is to get Cybercab out on the roads and integrated into the public Robotaxi fleet, one that will pick up real-world ride-hailers and give them a ride from Point A to Point B.
No matter which way you cut it, it appears Tesla is close to putting a vehicle with no steering wheel and no pedals on the road to help people travel autonomously.
You can ride along with us in our first Cybercab ride from the We, Robot event in October 2024. The video is embedded below:
🎥: Our FULL first ride in the @Tesla Cybercab pic.twitter.com/6gR7OgKRCz
— TESLARATI (@Teslarati) October 11, 2024
Tesla has revealed plans through permit submissions for a massive Robotaxi charging hub in Austin, Texas.
Tesla plans to build the Supercharger hub in multiple phases, with the second phase potentially introducing wireless induction charging, something the company has been developing for the Robotaxi fleet.
Initially, 48 Tesla Robotaxi-geared Superchargers will be built on a lot just across from the St. Elmo, Texas, Service Center. There are about 80 additional spots that will not be impacted by phase 1 of the construction process.
Filings show that the second phase of the project will turn those 80 additional spots into wireless charging for Robotaxi, but it might be an error. The Key Notes state that item 3 is listed as “V4 Charging Cabinet to Support 80 Wireless Chargers in Phase 2. However, the drawings point to V3 Cabinets that are already tied to Superchargers:
There are roughly 128 total spots in the lot, but it is unclear if they will all be used for charging based on what appears to be some sort of typo in the blueprint.
A new Robotaxi fleet charging hub is coming soon to Austin, Texas!!
Permits have been filed for the installation of 48 (V3) stalls in a vehicle storage lot across the road from Tesla’s St Elmo service center. pic.twitter.com/xwRgSWDqht
— MarcoRP (@MarcoRPi1) August 18, 2026
This is among the first Robotaxi charging hubs Tesla has started to develop, as it currently has four others planned throughout various areas: one in Phoenix, one in San Antonio, another in Irving, which will serve the Dallas-Fort Worth area, and another in Las Vegas.
These projects are necessary as Tesla expands its Robotaxi program. Now that preparations have started for the public launch of Cybercab, Robotaxi will likely be expanding aggressively, especially over the next two to three years.
Last night, The Information reported that Tesla was planning to launch Cybercab as soon as the end of August. Hours later, Tesla then announced it was launching a competition for fans to potentially ride in Cybercab during its first public rides.
Tesla’s plan to expand its charging infrastructure in the regions where Robotaxi will initially operate is great preparation for the expanding service. There is still a lot to do, including launching the Cybercab on time.
SpaceX achieves incredible milestone with Starlink program
Tesla is opening Cybercab rides to a select few
