News
NASA’s SLS Moon rocket almost aces vital prelaunch test on 7th try
Following several incomplete attempts in April, June, August, and September, NASA’s first Space Launch System (SLS) Moon rocket has almost aced a vital prelaunch test on the seventh try.
NASA says that “all objectives were met” during the ten-hour test, which wrapped up around 4:30 pm EDT (20:30 UTC) on Wednesday, September 21st. Despite the rocket running into multiple additional issues, some old and others new, the agency was confident enough in the preliminary results of the wet dress rehearsal (WDR) – deemed a “cryogenic demonstration test” – to reaffirm that it’s still working towards a third launch attempt as early as September 27th.
That launch date is not set in stone, but NASA also hasn’t ruled out the window after the latest round of SLS testing. The agency will host a press conference on Friday, September 23rd, to provide its final decision and offer more details about the seventh wet dress rehearsal.
Despite NASA’s apparent confidence after the test, which was admittedly smoother than most previous SLS tests at the launch pad, it was far from smooth. The immediate story of the “cryogenic demonstration test” dates back to the SLS Artemis I rocket’s second so-called “launch attempt” on September 3rd. During that attempt, the launch was aborted well before SLS was ready when NASA detected a major hydrogen fuel leak around one of the quick-disconnect umbilical panels that fuels and drains the rocket. Remote troubleshooting was unable to solve the problem, forcing NASA to stand down.
Over the last few weeks, teams inspected, tested, and repaired the faulty Tail Service Mast Umbilical (TSMU), preparing for a cryogenic proof test meant to verify that the issue was fixed. During that September 21st test, the TSMU still leaked significantly for the whole duration, but it did so more predictably and – unlike prior leaks – never violated the limits that would trigger a launch abort.
But near the end, a different umbilical panel developed a significant hydrogen leak that did violate those launch constraints, meaning that NASA would have likely had to stand down yet again if it had attempted to launch before completing additional testing. The test was completed successfully, but its goals and constraints were not the same as those facing a launch.
A NASA-developed rocket leaking hydrogen is unfortunately a tale as old as time. That the agency that struggled with hydrogen leaks throughout the 30-year career of the Space Shuttle appears to be just as flabbergasted by nearly identical problems on a new rocket – SLS – that has Shuttle ‘heritage’ on almost every square inch is not surprising, even if it is somewhat embarassing.
Liquid hydrogen fuel always has been and likely always will be a massive pain to manage in any rocket, but especially in a large rocket. As the smallest element in the universe, it is fundamentally leak-prone. Combined with the fact that it only remains liquid below the extraordinarily low temperature of -253°C (-423°F), generates ultra-flammable hydrogen gas as it continually attempts to warm to a more stable temperature, and naturally embrittles most metals, it’s an engineering nightmare by almost every measure.
For all that pain, hydrogen does provide rocket engineers exceptional efficiency when properly exploited, but even that positive aspect is often diminished by hydrogen’s ultra-low density. For rocket stages that have already reached orbit, hydrogen-oxygen propellant offers unbeatable efficiency. But for a rocket stage that will never be used in orbit, like the SLS core stage, hydrogen fuel is rarely worth the tradeoffs – a reality that SLS is unfortunately providing a strong reminder of.
Demonstrating the Groundhog Day-esque nature of NASA rockets and hydrogen leaks, the same leaky TSMU panel that aborted SLS’ September 3rd launch attempt (sixth WDR) and had to be fixed and retested on September 21st also caused a hydrogen leak that partially aborted the rocket’s third wet dress rehearsal attempt in April 2022. NASA then rolled the rocket back to the Vehicle Assembly Building (VAB), where workers spent almost two months inspecting and reworking the fuel TSMU and fixing other issues. During its first test (WDR #4) after rolling back to the pad in June, the same fuel TSMU leaked and NASA had to return the rocket to the VAB again to fix the problem.
The fuel TSMU then leaked on the SLS rocket’s first launch attempt (really WDR #5), but the problem was resolved and was not what caused NASA to stand down. It was, however, a primary reason behind NASA’s second aborted launch attempt (WDR #6). With any luck, the eighth time will be the charm.
News
Tesla Model X shocks everyone by crushing every other used car in America
The Model X is one of Tesla’s flagship models, the other being the Model S. Earlier this year, Tesla confirmed it would discontinue production of both the Model S and Model X to make way for Optimus robot production at the Fremont Factory in Northern California.
The Tesla Model X was the fastest-selling used vehicle in the United States in the first quarter of the year, crushing every other used car in America.
iSeeCars data for the first quarter shows that the Model X was the fastest-selling used car, lasting just 25.6 days on the market on average, two days better than that of the second-place Lexus RX 350h. The Cybertruck, Model Y, and Model S, in seventh, ninth, and thirteenth place, respectively, also made the list.
The Model X is one of Tesla’s flagship models, the other being the Model S. Earlier this year, Tesla confirmed it would discontinue production of both the Model S and Model X to make way for Optimus robot production at the Fremont Factory in Northern California.
Tesla brings closure to flagship ‘sentimental’ models, Musk confirms
Bringing closure to these two vehicles signaled the end of the road for the cars that have effectively built Tesla’s reputation for luxury and high-end passenger vehicles.
Relying on the sales of its mass market Model Y and Model 3, as well as leaning on the success of future products like the Cybercab, is the angle Tesla has chosen to take.
Teslas are also performing extremely well as a whole on the resale market. iSeeCars data shows that, “while the average price of a 1- to 5-year-old non-Tesla EV fell 10.3% in Q1 2026 year-over-year, the average price of a used Tesla was essentially flat at 0.1% lower across the same period. Traditional gas car prices dropped 2.8% during this same period.”
Additionally, market share for gas cars has dropped nearly 3 percent since the same quarter last year. Tesla has remained level, while the non-Tesla EV market share has increased 30 percent, mostly due to more models available.
Nevertheless, those non-Tesla EVs have seen their value drop by over 10 percent, while Tesla’s values have remained level.
Executive Analyst Karl Brauer said:
“Used electric vehicles without a Tesla badge have lost more than 10% of their value in the past year. This compares to stable values for Teslas and hybrids, and a modest 2.8% drop for traditional gasoline vehicles.”
Teslas, as well as non-luxury hybrids, are displaying the strongest resistance in the face of faltering demand, the publication says. But the more impressive performance is that of the Model X alone.
Tesla’s decision to stop production of the Model X may have played some part in the vehicle’s pristine performance in Q1. With the car already placed at a premium price point, used models are already more appealing to consumers. Perhaps second-hand versions were more than enough for those who wanted a Model X, and only a Model X.
Cybertruck
Tesla Cybertruck’s head-scratching trim sold terribly, recall documents reveal
The head-scratching offering was only available for a few months, and evidently, it did not sell very well, which we all suspected. New recall documents on the vehicle from the National Highway Traffic Safety Administration (NHTSA) now reveal just how poorly it sold.
After Tesla decided to build a Rear-Wheel-Drive Cybertruck trim back in 2025, which was void of many features and only featured a small discount.
The head-scratching offering was only available for a few months, and evidently, it did not sell very well, which we all suspected. New recall documents on the vehicle from the National Highway Traffic Safety Administration (NHTSA) now reveal just how poorly it sold.
The recall deals with a potentially separating wheel stud and potentially impacts 173 Cybertruck units with the 18-inch steel wheels. The Cybertruck RWD was the only trim level to feature these, and the 173 potentially impacted units represent a portion of the population of pickups. Therefore, it’s not the entire number of RWD Cybertruck sold, but it could show how little interest it gathered.
The NHTSA document states:
“On affected vehicles, higher severity road perturbations and cornering may strain the stud hole in the wheel rotor, causing cracks to form. If cracking propagates with continued use and strain, the wheel stud could eventually separate from the wheel hub.”
Only 5 percent are expected to be impacted, meaning less than 10 units will have the issue if the NHTSA and Tesla estimates are correct. Nevertheless, the true story here is how terribly the RWD Cybertruck sold.
Tesla ended production and stopped offering the RWD Cybertruck to customers last September. For just $10,000 less than the All-Wheel-Drive trim, Tesla offered the RWD Cybertruck with just one motor, textile seats instead of leather, only 7 speakers instead of 15, no Rear Touchscreen, no Powered Tonneau Cover for the truck bed, and no 120v/240v outlets.
For just $10,000 more, at $79,990, owners could have received all of those premium features, as well as a more capable All-Wheel-Drive powertrain that featured Adaptive Air Suspension. The discount simply was not worth the sacrifices.
Orders were few and far between, and sources told us that when it was offered, sales were extremely tempered because customers could not see the value in this trim level.
Even Tesla’s most loyal supporters thought the offering was kind of a joke, and the $10,000 extra was simply worth it.
News
Tesla Semi sends clear message to Diesel rivals with latest move
The truck is being built at a dedicated facility in Sparks, Nevada, just next to its Gigafactory Nevada facility.
Tesla has officially launched Semi production at what will be a mind-boggling rate of approximately 50,000 units per year.
The truck is being built at a dedicated facility in Sparks, Nevada, just next to its Gigafactory Nevada facility.
The company finally announced on April 29 that the first Tesla Semi truck has rolled off its new high-volume production line at the factory. This marks the transition from limited pilot builds to scaled manufacturing for the Class 8 all-electric heavy-duty truck, nearly nine years after its dramatic 2017 unveiling.
🚨 Tesla Semi mass production is underway in Nevada!
HUGE! https://t.co/ohgQIiI2bK pic.twitter.com/23GvWr8D27
— TESLARATI (@Teslarati) April 29, 2026
Tesla initially promised high-volume deliveries by 2019–2020, but battery supply constraints and prioritization for passenger vehicles delayed progress. The new 1.7-million-square-foot factory, purpose-built next to Gigafactory Nevada’s 4680 cell production lines, resolves those bottlenecks through deep vertical integration.
The Semi uses Tesla’s structural battery packs with cylindrical 4680 cells manufactured on-site. This integration enables efficient supply, reduced logistics costs, and the potential for high output. The factory is designed for an eventual annual capacity of approximately 50,000 trucks, positioning Tesla to address growing demand in long-haul freight electrification.
Tesla is using a redesigned Cybertruck battery cell to mitigate Semi challenges
Operating economics favor the Semi through dramatically lower fuel and maintenance costs compared to traditional diesel rigs, and companies involved in a pilot program for the Semi with Tesla have shown that.
Electricity is far cheaper than diesel on a per-mile basis, while the electric powertrain features fewer moving parts, reducing service intervals and lifetime expenses. Early deployments with customers like PepsiCo and others have validated these advantages in real-world service.
The Nevada factory’s ramp-up is targeted for full volume output before the end of June 2026, aligning with broader Tesla production goals for 2026. This includes parallel efforts on other new vehicles while expanding the Megacharger infrastructure to support widespread adoption.
By localizing battery and truck production, Tesla gains advantages in cost, quality control, and scalability that many competitors sourcing cells externally lack. The start of high-volume Semi production represents a pivotal step in Tesla’s strategy to electrify heavy transportation, potentially accelerating the shift toward zero-emission freight across North America and beyond.
As output increases, the Semi could reshape long-haul logistics with its combination of performance, efficiency, and sustainability.