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.
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Elon Musk
California city weighs banning Elon Musk companies like Tesla and SpaceX
A resolution draft titled, “Resolution Ending Engagement With Elon Musk-Controlled Companies and To Encourage CalPERS To Divest Stock In These Companies,” alleges that Musk “has engaged in business practices that are alleged to include violations of labor laws, environmental regulations, workplace safety standards, and regulatory noncompliance.”
A California City Council is planning to weigh whether it would adopt a resolution that would place a ban on its engagement with Elon Musk companies, like Tesla and SpaceX.
The City of Davis, California, will have its City Council weigh a new proposal that would adopt a resolution “to divest from companies owned and/or controlled by Elon Musk.”
This would include a divestment proposal to encourage CalPERS, the California Public Employees Retirement System, to divest from stock in any Musk company.
A resolution draft titled, “Resolution Ending Engagement With Elon Musk-Controlled Companies and To Encourage CalPERS To Divest Stock In These Companies,” alleges that Musk “has engaged in business practices that are alleged to include violations of labor laws, environmental regulations, workplace safety standards, and regulatory noncompliance.”
It claims that Musk “has used his influence and corporate platforms to promote political ideologies and activities that threaten democratic norms and institutions, including campaign finance activities that raise ethical and legal concerns.”
If adopted, Davis would bar the city from entering into any new contracts or purchasing agreements with any company owned or controlled by Elon Musk. It also says it will not consider utilizing Tesla Robotaxis.
Hotel owner tears down Tesla chargers in frustration over Musk’s politics
A staff report on the proposal claims there is “no immediate budgetary impact.” However, a move like this would only impact its residents, especially with Tesla, as the Supercharger Network is open to all electric vehicle manufacturers. It is also extremely reliable and widespread.
Regarding the divestment request to CalPERS, it would not be surprising to see the firm make the move. Although it voted against Musk’s compensation package last year, the firm has no issue continuing to make money off of Tesla’s performance on Wall Street.
The decision to avoid Musk companies will be considered this evening at the City Council meeting.
The report comes from Davis Vanguard.
It is no secret that Musk’s political involvement, especially during the most recent Presidential Election, ruffled some feathers. Other cities considered similar options, like the City of Baltimore, which “decided to go in another direction” after awarding Tesla a $5 million contract for a fleet of EVs for city employees.
Elon Musk
Starlink restrictions are hitting Russian battlefield comms: report
The restrictions have reportedly disrupted Moscow’s drone coordination and frontline communications.
SpaceX’s decision to disable unauthorized Starlink terminals in Ukraine is now being felt on the battlefield, with Ukrainian commanders reporting that Russian troops have struggled to maintain assault operations without access to the satellite network.
The restrictions have reportedly disrupted Moscow’s drone coordination and frontline communications.
Lt. Denis Yaroslavsky, who commands a special reconnaissance unit, stated that Russian assault activity noticeably declined for several days after the shutdown. “For three to four days after the shutdown, they really reduced the assault operations,” Yaroslavsky said.
Russian units had allegedly obtained Starlink terminals through black market channels and mounted them on drones and weapons systems, despite service terms prohibiting offensive military use. Once those terminals were blocked, commanders on the Ukrainian side reported improved battlefield ratios, as noted in a New York Post report.
A Ukrainian unit commander stated that casualty imbalances widened after the cutoff. “On any given day, depending on your scale of analysis, my sector was already achieving 20:1 (casuality rate) before the shutdown, and we are an elite unit. Regular units have no problem going 5:1 or 8:1. With Starlink down, 13:1 (casualty rate) for a regular unit is easy,” the unit commander said.
The restrictions come as Russia faces heavy challenges across multiple fronts. A late January report from the Center for Strategic and International Studies estimated that more than 1.2 million Russian troops have been killed, wounded, or gone missing since February 2022.
The Washington-based Institute for the Study of War also noted that activity from Russia’s Rubikon drone unit declined after Feb. 1, suggesting communications constraints from Starlink’s restrictions may be limiting operations. “I’m sure the Russians have (alternative options), but it takes time to maximize their implementation and this (would take) at least four to six months,” Yaroslavsky noted.
Elon Musk
SpaceX and xAI tapped by Pentagon for autonomous drone contest
The six-month competition was launched in January and is said to carry a $100 million award.
SpaceX and its AI subsidiary xAI are reportedly competing in a new Pentagon prize challenge focused on autonomous drone swarming technology, as per a report from Bloomberg News.
The six-month competition was launched in January and is said to carry a $100 million award.
Bloomberg reported that SpaceX and xAI are among a select group invited to participate in the Defense Department’s effort to develop advanced drone swarming capabilities. The goal is reportedly to create systems that can translate voice commands into digital instructions and manage fleets of autonomous drones.
Neither SpaceX, xAI, nor the Pentagon’s Defense Innovation Unit has commented on the report, and Reuters said it could not independently verify the details.
The development follows SpaceX’s recent acquisition of xAI, which pushed the valuation of the combined companies to an impressive $1.25 trillion. The reported competition comes as SpaceX prepares for a potential initial public offering later this year.
The Pentagon has been moving to speed up drone deployment and expand domestic manufacturing capacity, while also seeking tools to counter unauthorized drone activity around airports and major public events. Large-scale gatherings scheduled this year, including the FIFA World Cup and America250 celebrations, have heightened focus on aerial security.
The reported challenge aligns with broader Defense Department investments in artificial intelligence. Last year, OpenAI, Google, Anthropic, and xAI secured Pentagon contracts worth up to $200 million each to advance AI capabilities across defense applications.
Elon Musk previously joined AI and robotics researchers in signing a 2015 open letter calling for a ban on offensive autonomous weapons. In recent years, however, Musk has spoken on X about the strengths of drone technologies in combat situations.




