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SpaceX wiggles Starhopper’s Raptor engine, tests parts ahead of hover test debut

Repeating a test conducted in June with Raptor SN04, SpaceX tested Starhopper and Raptor SN06's thrust vectoring capabilities on July 12th. (NASASpaceflight - bocachicagal)

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On the evening of July 12th, SpaceX technicians put Starhopper’s freshly-installed Raptor – serial number 06 (SN06) – through a simple but decidedly entertaining test, effectively wiggling the engine in circles.

Designed to verify that Raptor’s thrust vectoring capabilities are in order and ensure that Starhopper and the engine are properly communicating, the wiggle test is a small but critical part of pre-flight acceptance and a good indicator that the low-fidelity Starship prototype is nearing its first hover test(s). Roughly 48 hours after a successful series of wiggles, Starhopper and Raptor proceeded into the next stage of pre-flight acceptance, likely the final more step before a tethered static fire.

Routine for all Falcon rockets, SpaceX’s exceptionally rigorous practice of static firing all hardware at least once (and often several times) before launch has unsurprisingly held firm as the company proceeds towards integrated Starhopper and Starship flight tests. Despite the fact that Raptor SN06 completed a static fire as recently July 10th, SpaceX will very likely put Starhopper and its newly-installed Raptor through yet another pre-flight static fire, perhaps its fourth or fifth test this month.

Although it would undoubtedly be easier, cheaper, and faster to skip that post-delivery static fire, it will simultaneously lower the risk of Raptor failing mid-flight and verify that Starhopper itself is healthy and ready for untethered hovering. Although SpaceX could likely live without Starhopper in the event that it’s lost during flight-testing, any failure capable of destroying the vehicle itself is at least as capable of severely damaging or completely destroying the spartan but still expansive test and launch facilities the company built over the course of several months.

SpaceX has been hard at work gradually building, expanding, and upgrading its South Texas launch facilities since December 2018. (NASASpaceflight – bocachicagal, 04/27/2019)

Would you like some testing with your testing?

Follow July 12th’s nighttime Raptor wiggle test, July 13th was mainly quiet and filled with inspections of Starhopper, Raptor, and other various work. The day after, however, SpaceX proceeded through several hours of propellant loading, ending with what looked like less energetic versions of the Raptor preburner ignition tests Starhopper previously performed with Raptor SN02.

In a staged-combustion engine like Raptor, getting from the supercool liquid oxygen and methane propellant to 200+ tons of thrust is quite literally staged, meaning that the ignition doesn’t happen all at once. Rather, the preburners – essentially their own, unique combustion chambers – ignite an oxygen- or methane-rich mixture, the burning of which produces the gas and pressure that powers the turbines that bring fuel into the main combustion chamber. That fuel then ignites, producing thrust as they exit the engine’s bell-shaped nozzle.

The first obvious test occurred around 7:30pm CT, July 14th. (LabPadre)
The second obvious test followed around 8:50 pm CT. (LabPadre)

Although the fireworks are so subtle that they are easily missed, the conditions inside the preburner – hidden away from view – are actually far more intense than the iconic blue, purple, and pink flame that exists Raptor’s nozzle. This is because the preburners have to nurture the conditions necessary for the pumps they power to fuel the main combustion chamber. Much like hot water will cool while traveling through pipes, the superheated gaseous propellant that Raptor ignites to produce thrust will also cool (and thus lose pressure) as it travels from Raptor’s preburner to the main combustion chamber.

Thus, if the head pressure produced in the preburners is too low, Raptor’s thrust will be (roughly speaking) proportionally limited at best. At worst, low pressure in the preburners can completely prevent Raptor from starting and running stably and can even trigger a “hard start” or shutdown that could damage or destroy the engine. As such, to preburners fundamentally have to operate at higher chamber pressures (and thus higher temperatures) than the main combustion chamber (the big firey bit at the end). According to Elon Musk, Raptor’s oxygen preburner has the worst of it, operating at pressures as high or higher than 800 bar (11,600 psi, 80 megapascals).

Coincidentally, this is roughly equivalent to the pressure at the bottom of the Pacific Ocean.

Starhopper and Raptor seen on the afternoon of July 14th, preparing for an evening of testing. (NASASpaceflight – bocachicagal)

In short, preburner testing is no less critical than full-on static fire testing with an engine like Raptor. July 14th’s test was also made doubly efficient due to the fact that preburner testing requires liquid propellant, which effectively makes the whole test a wet dress rehearsal (WDR) even before any engine ignition or partial ignition is involved. Per SpaceX moving from propellant loading to preburner/turbine testing, Starhopper is almost certainly healthy and operating as expected, an excellent sign that the ungainly vessel may be ready for a static fire of Raptor as early as 2pm CT, July 15th.

The memes, oh, the memes.

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Eric Ralph is Teslarati's senior spaceflight reporter and has been covering the industry in some capacity for almost half a decade, largely spurred in 2016 by a trip to Mexico to watch Elon Musk reveal SpaceX's plans for Mars in person. Aside from spreading interest and excitement about spaceflight far and wide, his primary goal is to cover humanity's ongoing efforts to expand beyond Earth to the Moon, Mars, and elsewhere.

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Cybertruck

Tesla Cybertruck gets a big price change on two of its three trims

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Credit: Tesla

Tesla Cybertruck trims saw a big price change, at least on two of the three available to consumers, as demand for the all-electric pickup appears to be increasing.

Tesla bumped up its Base All-Wheel-Drive trim level up to $74,990 from $69,990 and the Premium All-Wheel-Drive configuration from $79,990 to $84,990. The Cyberbeast price remains unchanged at $99,990.

Despite questions of demand for the truck, Tesla is bumping its two least expensive trims up $5,000 to signal that there are plenty of buyers. Although SpaceX has been buying Tesla Cybertruck units to utilize as company vehicles, it is no secret that the Cybertruck is among the most sought-after Tesla models out there.

The issue has always been pricing, at least for the most part. When Tesla initially launched the Cybertruck AWD at $59,990 a few months back, the company stated that price would remain intact for just ten days due to the influx of orders it received.

Cybertruck Sales: Is It the Product or Pricing?

Depending on who you ask, you will likely hear one of two explanations for relatively low Cybertruck sales: either the product itself or the pricing.

Yes, this is the best-selling all-electric pickup on the market. However, there are people who simply hate the look of it, which I understand, but do not agree with. Look is totally subjective, and I love the look of the Cybertruck.

Some people will not buy the Cybertruck because of the look, but I am under the impression that sales would be much better if this truck were priced lower; something that might not be possible considering Tesla’s need to make money on its products. When it was unveiled in 2019, its most expensive trim level was $69,990. Now, the cheapest trim level is more expensive than that.

I would be in a Cybertruck if it were more affordable. I LOVE my Model Y, but Cybertruck is the best vehicle Tesla makes, and it’s not particularly close. Even in the base model, the steer-by-wire, the space, storage, and performance make it more desirable than the Model Y to me. I cannot be the only Tesla owner without a Cybertruck who feels this way.

If you’re interested in buying a Tesla vehicle, use my referral link.

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Energy

Tesla Semi factory is getting a celebration nobody expected

Tesla will inaugurate its Nevada Semi factory September 24, five months after production quietly began ramping.

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Tesla says it will officially inaugurate its new Semi factory in Nevada next month. The Tesla Semi account posted the announcement on X, sharing a graphic titled “Semi Rollout” with a date of September 24. No further details were given about the format of the event or who would attend.

While Tesla’s dedicated Semi plant in Sparks, adjacent to Gigafactory Nevada, opened back in April, with the first trucks rolling off the high volume line on April 29, the timing for the factory inauguration comes at a surprise. The ribbon cutting event five months into production is a break from how Tesla has usually handled its other factories, where the first truck or car off the line typically served as the milestone moment.

The 1.7 million square foot factory was built as part of a $3.6 billion expansion Tesla announced in early 2023, and it shares a site with the battery cell lines that feed the Semi’s structural pack, a decision meant to remove the supply bottleneck that delayed the truck for years. The plant is designed for 50,000 trucks a year at full ramp. Semi program director Dan Priestley has said production “is now ramping” rather than claiming it has reached scale.

Nine years passed between the Semi’s 2017 unveiling and this stage of production, with the truck slipping from an original 2019 target through hand built pilot units for PepsiCo and a slow build out of the Nevada plant. An inauguration event now gives Tesla a stage to talk up that ramp and reset expectations for how many trucks it can begin delivering at scale.

The September date also lines up with the Semi’s next milestone. Tesla confirmed the truck is heading to Europe with a full unveiling at the IAA Transportation trade show in Hannover, Germany, running September 15 through 20. Between the Nevada event and the Hannover reveal, Tesla has roughly a week and a half in September to make the case that the Semi is now a truck being built and sold on two continents rather than tested in a handful of fleets.

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Elon Musk

Elon Musk just set a condition that could end Falcon 9 as we know it

Elon Musk says SpaceX will finally retire Falcon 9 once Starship flies reliably every week.

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Elon Musk gave the clearest timeline yet for retiring Falcon 9, SpaceX’s workhorse rocket.

The comment came in a reply on X, where Musk wrote that “once Starship is flying reliably several times per week, it makes sense to shift super scarce SpaceX engineering and production resources to Starship to get launch rate to several times per day, which means winding down Falcon.” He was responding to physicist Casey Handmer, who noted that NASA is reportedly uneasy about SpaceX phasing out Falcon after building what Handmer called the most successful launcher ever, with the fleet nearing 1,000 total launches.


Falcon 9 is still SpaceX’s busiest vehicle by far. The company is on pace for roughly 140 to 145 Falcon flights this year, following 165 in 2025, president Gwynne Shotwell told Time earlier in 2026. She has already said Falcon flights would “tail off” as Starship comes online, while reports indicate that SpaceX has stopped booking new Falcon 9 launches past 2028 and halted production of some expendable Falcon hardware, according to Bloomberg.

It’s worth noting that Musk’s post is a condition, and not a countdown on when Falcon will retire. Starship has not yet flown weekly, let alone daily. Its most recent flight in July ended with a soft splashdown in the Indian Ocean, a milestone Musk pointed to earlier this month when he said the vehicle’s heat shield problem was effectively solved. SpaceX towed that ship to Christmas Island for inspection, and the next flight, Flight 14, is aimed at putting Starship into orbit for the first time. A tower catch attempt for the upper stage has been pushed back to what Musk has called “a few months” away.

SpaceX and a new Trump order that could rewrite the next decade of launches

The gap between Falcon’s role today and Starship’s promised role tomorrow matters most to NASA. Falcon and its Dragon capsule remain the only way the agency rotates astronauts to and from the International Space Station, and Starship is not certified to carry NASA crews. Musk’s post did not address how that handoff would work if Falcon winds down before a crew-rated Starship variant exists. The timing lines up with Musk’s other recent Starship comments. Two days before the Falcon post, he told a different X user that SpaceX is aiming for more than 30 Starship launches a day by 2030, or roughly 10,000 a year, a figure tied to the Trump administration’s new push for higher national launch cadence. Falcon, which took over a decade to reach its first 100 launches, was never built to approach that kind of volume.

For now, Falcon 9 keeps flying at a near-record pace while Starship works to prove it can do the job Musk has already picked out for it.

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