SpaceX
SpaceX CEO Elon Musk: Starship prototype to have 3 Raptors and “mirror finish”
Taking to Twitter once more to reveal additional information about SpaceX’s radically changing BFR/Starship prototype program, CEO Elon Musk has made an unexpected visit to the company’s South Texas BFR testing facilities to oversee rapid progress with a low-fidelity hop test prototype of the orbital Starship spacecraft.
Included in a handful of replies that followed the tweeted image, Musk described some of the key advantages of a stainless steel Starship – including mirror-like thermal reflectivity for hot reentries and a “usable” strength-to-mass ratio superior to carbon fiber – as well as features of prototype cousin.
Stainless Steel Starship pic.twitter.com/rRoiEKKrYc
— Elon Musk (@elonmusk) December 24, 2018
While the CEO did imply on Saturday that the Mars-focused Raptor engine had been what he described as “radically redesigned”, Musk’s statement that the Starship hopper will feature three Raptor engines does at least set a lower bound for the ship’s maximum gross takeoff weight when the time comes for it to take flight.
Yes. Radically redesigned Raptor ready to fire next month.
— Elon Musk (@elonmusk) December 22, 2018
While the suggestion that Raptor’s turbopumps (basically fuel pumps) would need at least 100,000 HP per engine seems to indicate that the flight design’s thrust has been appreciably uprated, a past figure of ~2000 kN (450,000 lbf) per engine suggests that Starship V0.1 could weigh as much as an entire Falcon 9 Block 5 rocket (~1.2 million pounds, 550,000 kg) and still having a solid 80-100% of Falcon 9’s liftoff thrust. Put simply, the rocket that appears to be coming together in the boonies of South Texas could rival almost any other liquid fuel rocket booster in service, while still being the testbed for BFR’s upper stage alone.
While it’s ambiguous if several additional comments applied to the Starship prototype, the final product, or both, Musk also indicated that some of the biggest benefits of a shift away from carbon composites to stainless steel would be relative ease with which the material handles extreme heating. Thanks to the fact that stainless steel can ultimately be polished to mirror-like levels of reflectivity and that mirrors are some of the most efficient reflectors of thermal energy (heat), shiny and unpainted steel would ultimately perform far better than carbon composites and could end up requiring “much less” heat shielding for the same performance.
- ¯\_(ツ)_/¯ (bocachicagal – NASASpaceflight)
- A conspicuous nosecone appears to have arisen inside SpaceX’s new Boca Chica tent, adjacent to what looks like a water tower with tube legs. (bocachicagal – NASASpaceflight)
- Boca Chica, 12/23/18. (NASASpaceflight /u/bocachicagal)
- It remains to be seen if BFR can be made as reusable and reliable as it will need to be to sustainably support interplanetary humans. (SpaceX)
- Starship – in its 2018 design iteration – seen landing on Mars atop pillars of Raptor flame. (SpaceX)
Perhaps most unintuitive is the fact that steel can apparently beat carbon composites when it comes to usable strength-to-weight ratios at supercool temperatures. According to Musk, steel also performs “vastly better” at high temperatures and appreciably better at room temperatures. A comment made on Saturday may lend additional credence to what seems at face value to contradict basic material intuition – at least some of the stainless steel SpaceX is examing would be a special (presumably SpaceX-engineered) alloy that has undergone what is known as cryogenic treatment, in which metals are subjected to extremely cold conditions to create some seriously unintuitive properties. Ultimately, cold-formed/worked or cryo-treated steel can be dramatically lighter and more wear-resistant than traditional hot-rolled steel.
Usable strength/weight of full hard stainless at cryo is slightly better than carbon fiber, room temp is worse, high temp is vastly better
— Elon Musk (@elonmusk) December 24, 2018
Combined with advanced new alloys and a uniquely strong handle on working with supercool propellant (likely transferable to cold-forming steel), SpaceX and CEO Elon Musk could have a true breakthrough on their hands, especially if it turns out that a great deal of deep thought, analysis, and refinement fed into these “radical” design changes. With Starship Alpha’s hop tests potentially beginning as early as March 2019, we won’t have long to wait to find out.
For prompt updates, on-the-ground perspectives, and unique glimpses of SpaceX’s rocket recovery fleet check out our brand new LaunchPad and LandingZone newsletters!
Elon Musk
Elon Musk sends first warning to SpaceX short sellers
In a pointed message on X, Elon Musk warned that firms maintaining significant short positions in SpaceX over time face “very low” survival probability.
The statement comes amid post-IPO volatility for the rocket company, now trading under the ticker $SPCX.
The survival probability of firms who maintain a significant short position in SpaceX over time is very low
— Elon Musk (@elonmusk) July 17, 2026
Five weeks after what was described as the largest IPO in history, the stock had fallen roughly 30% from its peak above $2.6 trillion, briefly surpassing Microsoft and Amazon in market value. Short sellers celebrated gains of about $8.7 billion, but Musk’s reply underscores his long-term conviction.
The warning directly echoes a detailed bullish analysis arguing that Starship’s cost reductions could unlock a multi-trillion-dollar space economy. Projects ranging from solar power beamed from orbit and asteroid mining to orbital data centers and Mars terraforming were projected to create over $100 trillion in new market capitalization.
In this vision, SpaceX acts as the essential infrastructure provider, akin to AWS for cloud computing, capturing monopoly-like revenues from launches, crew transport, and data traffic across a rapidly expanding frontier.
This is far from the first time Musk has targeted short sellers. With Tesla, he has repeatedly framed persistent bears as destined for major losses. In July 2024, Musk declared that once Tesla achieves full autonomy and volume production of Optimus robots, “anyone still holding a short position will be obliterated. Even Gates,” referencing Microsoft co-founder Bill Gates’ reported short bets.
Elon Musk reveals what Tesla stock surge could do to Bill Gates
Earlier, in 2018, he taunted shorts that they had “about three weeks before their short position explodes,” a remark followed by sharp stock gains. Musk has also called short selling “value destroying” and once suggested it “should be illegal,” viewing it as betting against innovation and progress.
Critics often dismiss Musk’s optimism as hype, especially when near-term metrics like quarterly deliveries or stock fluctuations disappoint.
Yet his pattern remains consistent: framing short positions against his companies as fundamentally misjudging exponential technological leaps. For SpaceX shorts, the message is clear: betting against multi-planetary ambitions and the infrastructure monopoly they enable carries existential risk for the firms involved.
As Musk and supporters see it, the space economy’s upside dwarfs Earth-bound valuation models, making today’s dips temporary in a decades-long ascent.
News
SpaceX adjusts Starship Flight 13 test launch target date once again
SpaceX has updated its target for the thirteenth integrated flight test of Starship, aiming for as early as Thursday, July 23. The 90-minute launch window opens at 5:45 p.m. CT from the company’s Starbase facility in South Texas.
The target flight was initially rescheduled for today, but SpaceX pushed it back again.
This latest adjustment follows an aborted attempt earlier in the week and reflects the iterative, rapid-development approach that has defined the Starship program. With the vehicle already stacked and ground teams making final preparations, the mission represents another step toward proving the full reusability of the world’s most powerful rocket system.
Now targeting to launch Starship’s thirteenth flight test as early as Thursday, July 23 → https://t.co/Rp7VwBzpWx pic.twitter.com/Y0YNzfc5zk
— SpaceX (@SpaceX) July 19, 2026
The original launch attempt on July 16 was scrubbed at T-0 when several Raptor engines on the Super Heavy booster failed to ignite properly. The automatic abort system triggered just as the engines began their startup sequence, preventing liftoff.
SpaceX CEO Elon Musk confirmed that some engines did not start as expected, prompting the decision to replace two Raptors on Booster 20 to ensure reliability. The issue occurred despite a successful full-duration static fire earlier, highlighting the complexities of coordinating 33 engines under flight conditions.
This cautious approach underscores SpaceX’s commitment to safety amid an aggressive test cadence.
Flight 13 builds directly on the lessons from Flight 12 in May 2026. The Super Heavy booster’s primary goals include a successful liftoff, ascent, stage separation, boostback burn, and controlled splashdown in the Gulf of America.
Hardware and software modifications address the off-nominal flip and boostback burn problems from the prior flight, where propellant slosh and engine relight issues led to an uncontrolled impact.
For the Starship upper stage, objectives include deploying 20 operational Starlink V3 satellites, the first real payload of this type, performing a single Raptor engine relight in space, and executing a controlled entry, descent, and splashdown in the Indian Ocean. Propulsion upgrades aim to improve engine-out capability after one vacuum Raptor was lost on Flight 12.
Additional test elements focus on heat shield performance. Six satellites carry cameras to image the tiles during flight, while white-painted tiles and upgraded attachments on flaps and the aft skirt will gather data for future reusability.
The FAA completed its mishap investigation into Flight 12 earlier this month, clearing the regulatory path.
This suborbital mission, the second with V3 vehicles, advances Starship toward operational missions, including potential crewed flights and support for NASA’s Artemis program. Success would mark significant progress in rapid reusability and satellite deployment from the massive system.
News
Elon Musk debunks $52 billion SpaceX-NVIDIA GPU deal
Elon Musk dismissed reports claiming SpaceX had placed a massive order for NVIDIA GPUs worth $52 billion. The denial came hours after Taiwanese media, citing unnamed industry sources, reported that SpaceX planned to acquire approximately 13,000 AI server racks, equating to roughly 1 million GB300 GPUs, from Foxconn.
Each rack was estimated at around $4 million, with deliveries potentially starting in late 2025.
The story suggested this would mark SpaceX’s first major foray into Foxconn-manufactured NVIDIA hardware, breaking from suppliers like Supermicro and Dell. Musk responded bluntly on X:
This is fake news
— Elon Musk (@elonmusk) July 20, 2026
Despite the denial, the rumored scale aligns with SpaceX’s explosive growth in AI infrastructure. NVIDIA’s GB300 (successor to the GB200 NVL) racks deliver unprecedented performance for large-scale training and inference. A $52 billion commitment would dwarf most corporate AI budgets and provide the compute muscle needed for frontier models.
SpaceX already operates gigawatt-scale terrestrial clusters like Colossus in Memphis, Tennessee, and has monetized them aggressively through leasing deals.
SpaceX’s newest Starmind will make earth data centers obsolete
Major customers include Anthropic (paying ~$1.25 billion monthly for 220,000+ GPUs), Google (~$920 million monthly for 110,000 GPUs), and Reflection AI. These arrangements are projected to generate tens of billions in annual revenue, far outpacing traditional SpaceX businesses.
Such an investment would fuel internal AI efforts, particularly Grok models under the integrated SpaceXAI division, while supporting ambitious orbital data center plans. SpaceX envisions launching thousands of AI-optimized satellites powered by solar energy and cooled in space, bypassing terrestrial power and land constraints.
This “Starmind” constellation could position the company as a leader in space-based computing.
SpaceX as an Emerging AI Powerhouse
Once primarily known for reusable rockets and Starlink satellite internet, SpaceX has transformed into a multifaceted AI player.
The 2026 acquisition of xAI integrated Grok development directly into the company. Starlink’s low-latency global network complements massive compute clusters, enabling efficient data flow for training and serving AI models.
Musk has long argued that AI scaling demands solutions beyond Earth, citing things like real estate and electricity limits on the ground.
While the Foxconn deal may not be in the cards, SpaceX’s trajectory is continuing on the path of blending aerospace engineering with hyperscale AI to dominate both launches and intelligence infrastructure.




