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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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Starlink achieves major milestones in 2025 progress report
Starlink wrapped up 2025 with impressive growth, adding more than 4.6 million new active customers and expanding service to 35 additional countries, territories, and markets.
Starlink wrapped up 2025 with impressive growth, adding more than 4.6 million new active customers and expanding service to 35 additional countries, territories, and markets. The company also completed deployment of its first-generation Direct to Cell constellation, launching over 650 satellites in just 18 months to enable cellular connectivity.
SpaceX highlighted Starlink’s impressive 2025 progress in an extensive report.
Key achievements from Starlink’s 2025 Progress
Starlink connected over 4.6 million new customers with high-speed internet while bringing service to 35 more regions worldwide in 2025. Starlink is now connecting 9.2 million people worldwide. The service achieved this just weeks after hitting its 8 million customer milestone.
Starlink is now available in 155 markets, including areas that are unreachable by traditional ISPs. As per SpaceX, Starlink has also provided over 21 million airline passengers and 20 million cruise passengers with reliable high-speed internet connectivity during their travels.
Starlink Direct to Cell
Starlink’s Direct to Cell constellation, more than 650 satellites strong, has already connected over 12 million people at least once, marking a breakthrough in global mobile coverage.
Starlink Direct to Cell is currently rolled out to 22 countries and 6 continents, with over 6 million monthly customers. Starlink Direct to Cell also has 27 MNO partners to date.
“This year, SpaceX completed deployment of the first generation of the Starlink Direct to Cell constellation, with more than 650 satellites launched to low-Earth orbit in just 18 months. Starlink Direct to Cell has connected more than 12 million people, and counting, at least once, providing life-saving connectivity when people need it most,” SpaceX wrote.
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Tesla Giga Nevada celebrates production of 6 millionth drive unit
To celebrate the milestone, the Giga Nevada team gathered for a celebratory group photo.
Tesla’s Giga Nevada has reached an impressive milestone, producing its 6 millionth drive unit as 2925 came to a close.
To celebrate the milestone, the Giga Nevada team gathered for a celebratory group photo.
6 million drive units
The achievement was shared by the official Tesla Manufacturing account on social media platform X. “Congratulations to the Giga Nevada team for producing their 6 millionth Drive Unit!” Tesla wrote.
The photo showed numerous factory workers assembled on the production floor, proudly holding golden balloons that spelled out “6000000″ in front of drive unit assembly stations. Elon Musk gave credit to the Giga Nevada team, writing, “Congrats on 6M drive units!” in a post on X.
Giga Nevada’s essential role
Giga Nevada produces drive units, battery packs, and energy products. The facility has been a cornerstone of Tesla’s scaling since opening, and it was the crucial facility that ultimately enabled Tesla to ramp the Model 3 and Model Y. Even today, it serves as Tesla’s core hub for battery and drivetrain components for vehicles that are produced in the United States.
Giga Nevada is expected to support Tesla’s ambitious 2026 targets, including the launch of vehicles like the Tesla Semi and the Cybercab. Tesla will have a very busy 2026, and based on Giga Nevada’s activities so far, it appears that the facility will be equally busy as well.
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Tesla Supercharger network delivers record 6.7 TWh in 2025
The network now exceeds 75,000 stalls globally, and it supports even non-Tesla vehicles across several key markets.
Tesla’s Supercharger Network had its biggest year ever in 2025, delivering a record 6.7 TWh of electricity to vehicles worldwide.
To celebrate its busy year, the official @TeslaCharging account shared an infographic showing the Supercharger Network’s growth from near-zero in 2012 to this year’s impressive milestone.
Record 6.7 TWh delivered in 2025
The bar chart shows steady Supercharger energy delivery increases since 2012. Based on the graphic, the Supercharger Network started small in the mid-2010s and accelerated sharply after 2019, when the Model 3 was going mainstream.
Each year from 2020 onward showed significantly more energy delivery, with 2025’s four quarters combining for the highest total yet at 6.7 TWh.
This energy powered millions of charging sessions across Tesla’s growing fleet of vehicles worldwide. The network now exceeds 75,000 stalls globally, and it supports even non-Tesla vehicles across several key markets. This makes the Supercharger Network loved not just by Tesla owners but EV drivers as a whole.
Resilience after Supercharger team changes
2025’s record energy delivery comes despite earlier 2024 layoffs on the Supercharger team, which sparked concerns about the system’s expansion pace. Max de Zegher, Tesla Director of Charging North America, also highlighted that “Outside China, Superchargers delivered more energy than all other fast chargers combined.”
Longtime Tesla owner and FSD tester Whole Mars Catalog noted the achievement as proof of continued momentum post-layoffs. At the time of the Supercharger team’s layoffs in 2024, numerous critics were claiming that Elon Musk was halting the network’s expansion altogether, and that the team only remained because the adults in the room convinced the juvenile CEO to relent.
Such a scenario, at least based on the graphic posted by the Tesla Charging team on X, seems highly implausible.
Starlink achieves major milestones in 2025 progress report
Tesla Giga Nevada celebrates production of 6 millionth drive unit
