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SpaceX to use superalloys in Mars rocket Raptor engines, says Elon Musk
A few days after he touched upon methods of creating BFR propellant on Mars, SpaceX CEO Elon Musk mentioned in a tweet that the launch company was using cutting-edge combinations of metals (known as superalloys) to ensure the efficiency and reliability of its Raptor rocket engine, a critical requirement for BFR to enable sustainable colonization of Mars.
In response to a tweeted question about types of metal alloys currently in use at SpaceX, Musk briefly delved into the complexities of building BFR’s propulsion system, particularly with respect to alloys capable of surviving the intense conditions inside a rocket engine:
“[SpaceX is using] SX 300 & soon SX 500. Kind of a modern version of Inconel superalloys. High strength at temperature, extreme oxidation resistance. Needed for ~800 atmosphere, hot, oxygen-rich turbopump on Raptor rocket engine.” – Elon Musk
There’s a lot to break down for the layperson in Musk’s tweet. First and foremost, commenters (your author included) immediately jumped to the conclusion that “SX 300/500” referred to some sort custom SpaceX material, given that SX is a frequent shorthand for SpaceX used in the enthusiast community. In reality, it was quickly discovered that the requirements Musk described for the material – namely “high strength at temperature [&] extreme oxidation resistance” – were nearly the exact same qualities of single-crystal superalloys, extremely advanced metal formulations also notated as SC or SX. It’s quite the apt coincidence that SpaceX will apparently rely on SX alloys for critical components of BFR propulsion.
A 2017 test-firing of the mature development Raptor, roughly 50% less powerful than the full-scale system. (SpaceX)
Single-crystal superalloys employ small amounts of exotic elements in order to better ensure truly unusual crystal formation in metal structures. In the case of SX alloys, the optimal result is a monolithic metal structure that effectively has no visible grain (think wood grain but in metal) – the resulting metal would be a huge monolithic crystal, in other words, uniform down to a near-atomic level. These SX superalloys are already used regularly for industrial applications requiring the ability to reliably operate in extremely corrosive high-pressure, high-temperature environments for long periods of time, most frequently seen in gas turbines for energy generation and airplane propulsion.
Per Musk, SpaceX intends to take those alloys a step further, developing its own SX-300 and SX-500 iterations for the purpose of building a reliable, robust turbopump for the Raptor propulsion system. In pursuit of the greatest possible efficiency, Raptor’s turbopump will run oxygen-rich, meaning that the inherently imperfect combustion process will lean towards excess oxygen in the exhaust, rather than excess methane. In simple terms, this choice is partially motivated by the fact that oxygen molecules are slightly lighter than methane molecules (15.999u vs. 16.04u). More importantly, the higher the pressure in the turbopump, the higher the pressure in Raptor’s combustion chamber, which directly correlates with more efficient combustion and thus a more efficient rocket engine overall. All improvements to its subcomponents will inherently end up benefiting SpaceX’s BFR booster and spaceship, the latter of which is already nearing initial prototype construction.
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- SpaceX’s current Texas facilities feature a test stand for Raptor, the engine intended to power BFR and BFS to Mars. (SpaceX)
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- SpaceX’s Raptor proceeds through the complex process of ignition. (SpaceX)
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- SpaceX’s subscale Raptor engine has completed more than 1200 seconds of testing in less than two years. (SpaceX)
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- SpaceX’s three-bay Raptor test stand as of April 17. The middle bay is currently home to the subscale Raptor test program. (Aero Photo)
While SpaceX cut its original Raptor specifications by roughly 50% compared to its 2016 goals, it appears that the company’s ambitions for the downsized Raptor are smaller in name only. In a May 2018 presentation, Chief of Propulsion Tom Mueller foreshadowed those future ambitions while humbly acknowledging that the Merlin 1D powering Falcon 9 and Heavy is already a masterpiece of engineering: “Merlin holds the thrust to weight record for now… but Raptor’s coming.”
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Elon Musk
SpaceX President to gift Trump Accounts her SpaceX stock
Gwynne Shotwell’s 2 million SpaceX shares are headed to children’s Trump Accounts starting this December.
SpaceX President Gwynne Shotwell said Friday that more than 2 million SpaceX shares belonging to her and her husband, Robert, will be distributed to children’s Trump Accounts in December, turning a pledge she made over the summer into an actual transfer. “Robert and I are thrilled that our gift of over 2 million shares of SpaceX stock will be distributed to children’s Trump accounts in December!” Shotwell wrote on X, adding that the shares are “transferring to escrow as we speak.”
The first round goes to children aged 11 to 17 who live in ZIP codes where the median family income is $57,000 or less, along with kids in ZIP codes with too few residents for the Census to report that figure. Shotwell said those families should receive a notice by Monday, Reuters reported.
A second gift is expected to be finalized in the next few weeks. That round will cover eligible children in military families serving overseas, children in foster care, and more kids in Texas counties near the Shotwells’ home where median family income is $90,000 or less. Elon Musk replied to the announcement with “Cool” and a heart emoji.
Shotwell first announced the donation on July 6, less than a month after SpaceX priced its record IPO at $135 per share on the Nasdaq. IPO filings showed Shotwell owned about 12.6 million SpaceX shares, Quartz reported at the time, which makes the gift roughly one sixth of her stake. At the roughly $146 per share used to value Musk’s own pledge earlier this month, 2 million shares are worth about $290 million.
How the stock would actually reach the accounts had been an open question since July. Treasury guidance acknowledged that stock donations could flow into Trump Accounts, but it did not explain the mechanics for a program whose contributions default into an S&P 500 index fund. Shotwell thanked the Treasury, the IRS, the Dell Foundation, Greater Horizons, Invest America and the law firms Morgan Lewis and Gibson Dunn for “working over the past few months to make this happen.”
The transfer also works as a dry run for a far larger gift. On October 19, Musk said he would give one of his SpaceX shares to every kid in America next year and called it “the first of many.” With roughly 72 million children in the country, that pledge is worth about $10.5 billion. President Donald Trump thanked Musk the same day and said the shares would go through Trump Accounts, though neither SpaceX nor the Treasury has published how or when that distribution will happen.
Shotwell’s recipients also fill a gap in the program itself. Trump Accounts launched on July 4, and the $1,000 Treasury deposit only goes to babies born between 2025 and 2028. Teenagers aged 11 to 17 receive no government seed money, so for many of the families getting a notice on Monday, SpaceX stock will be the first asset in the account. The accounts convert into retirement accounts when the child turns 18.
Tesla Full Self-Driving is now the centerpiece of the company’s newly revised Referral Program, which launched on October 29.
Instead of referring people to purchase vehicles and the referrer receiving $250 in Tesla Credit, the new program now incentivizes Full Self-Driving subscriptions.
If a Tesla owner is on an FSD trial and uses a referral code to subscribe to Full Self-Driving, the person whose Referral Link was used will receive one month of FSD (Supervised). Their code can be utilized 12 times per year, with January 1 marking the reset date.
Realistically, this means that if your Referral Code is used by 12 Tesla owners on an FSD trial, you will receive a full year of FSD for free.
🚨 Here is Tesla’s new Referral Program for Full Self-Driving (Supervised):
When someone subscribes to FSD using your link, you’ll get a month free. Up to a year of FSD is available to you for free!
If you’d like to use my link: https://t.co/g00IX9OCE3 https://t.co/GFBzEO2jjS
— TESLARATI (@Teslarati) October 30, 2026
The previous program made it pretty difficult to get referrals; buying a vehicle is obviously a much larger financial strain than subscribing to Full Self-Driving for a month.
Of course, the previous Referral Program also offered a tangible benefit: $250 in credits you could use on Service, Supercharging, or anything in the Tesla Shop. It truly could pay for someone’s travel for a year. It recently bought me a new backpack and a T-shirt.
However, this new program is much more attainable for those who do not have a massive online presence of a slew of friends in the Tesla community who will use the code and max out subscriptions for vehicle purchases.
Woke up to maxed out Referrals! Thank you guys, that’s awesome!
Share your referral link below so others can use it! https://t.co/kesbwTcoTV
— TESLARATI (@Teslarati) October 30, 2026
The Full Self-Driving suite will now be the keystone of the Referral Program, which makes it more inclusive and more fun for everyone with an awesome benefit.
It also gives the impression that Tesla is truly focused on FSD subscriptions, something that saw a tremendous increase in volume in Q3, as 75 percent of deliveries for the quarter came with an FSD subscription attached.
Full Self-Driving data is so instrumental to the suite’s improvement that this kind of program benefits Tesla as much as it does the consumer.
Elon Musk
Tesla made napping in a Robotaxi easier with its latest update
Tesla’s quiet mode reaches Model Y Robotaxis, blacking out the screen for riders wanting rest.
Tesla’s quiet mode, the setting that blacks out the screen for riders who want to rest, has moved beyond the Cybercab. A video posted Thursday by Spencer (@scotsrule08) shows the feature running in a Model Y Robotaxi on a night ride that appears to be in Dallas.
New quiet mode now on @Robotaxi https://t.co/2cM2eM9NeN — Spencer (@scotsrule08) October 29, 2026
The rider taps a small crescent moon icon in the bottom right corner of the map screen. The map, media player, app shortcuts and Grok prompt disappear, leaving a dark display with “Arriving soon,” the destination and a line reading “Tap display to exit quiet mode.” Controls a passenger may still need, including Pull Over, cabin temperature, volume and Support, stay visible. One tap anywhere brings the full map back.
Quiet mode first showed up in the Cybercab last week, which Teslarati reported alongside a new rear camera view. Tesla has been trimming cabin noise in other ways too. On October 25, Spencer reported that Robotaxi turn signals now chime for the first four blinks and then go silent. Tesla has not published release notes for either change.
Elon Musk has been pitching this use for more than a decade. In October 2014, he said that “maybe five or six years from now I think we’ll be able to achieve true autonomous driving where you could literally get in the car, go to sleep and wake up at your destination,”
By 2017 he was setting a higher bar. Speaking at TED, Musk said the hard part was not making self-driving work 99.9 percent of the time, “because, like, if a car crashes one in a thousand times, then you’re probably still not going to be comfortable falling asleep. You shouldn’t be, certainly.”
Owners asked for something similar in their own cars. In December 2019, a Tesla owner requested a Nap Mode that would keep the climate running and wake the occupant with an alarm, and Musk answered “Ok,” as Teslarati covered at the time.
The line returned when the Cybercab was unveiled at the We, Robot event in October 2024. “We’ll move from supervised Full Self-Driving to unsupervised Full Self-Driving, where you can fall asleep and wake up at your destination,” Musk said. On Tesla’s first quarter earnings call in April 2025, he called it the deciding measure: “The acid test is, can you go to sleep in your car and wake up in your destination and I’m confident that will be available in many cities in the US by the end of this year,”
Tesla has run driverless Model Y rides in Dallas and Houston since April, so a passenger dozing off on the way home is now a realistic use of the button. Tesla is also offering new riders a free first trip in both cities, according to an in-app screen shared by tracker Ethan McKanna, and said on its third quarter call that Cybercab rides would launch in Dallas next month.
SpaceX President to gift Trump Accounts her SpaceX stock
Tesla Full Self-Driving becomes main pillar of new Referral Program
