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Stoke Space to build SpaceX Raptor engine’s first real competitor

Stoke Space has begun testing parts of an engine similar to SpaceX's famous Raptor.

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Seattle startup Stoke Space has revealed plans to develop an efficient rocket engine similar to the Raptors that power SpaceX’s Starship.

Formed in October 2019, Stoke Space secured its first significant round of funding – $9.1 million – less than three years ago. At that time, CEO and co-founder Andy Lapsa says that the startup had just five employees, no permanent workspace, and a “barren field” for a test site. Within 18 months, Stoke Space had turned that empty field into an impressive test facility, conducted numerous component tests, and assembled its first full-scale rocket engine – an exotic UFO-like device unlike any seen before.

It also raised another $65 million – enough funding to begin earnestly developing a potentially revolutionary rocket capable of launching more than 1.65 tons (~3600 lb) into orbit for less than half a million dollars. To realize that extremely ambitious goal, Stoke Space has taken the even more ambitious step of attempting to make the first rocket it develops fully reusable. Simultaneously, the company has incorporated several exotic technologies into that rocket, recently culminating in a surprise announcement that it will attempt to develop one of the most difficult types of engines to power that rocket’s booster stage.

Full-flow staged combustion

At the end of an extended interview and tour with YouTuber Tim Dodd (The Everyday Astronaut), CEO Andy Lapsa revealed that Stoke Space has decided to build a full-flow staged combustion (FFSC) engine for the first stage of its reusable rocket. FFSC is the most efficient type of combustion cycle available for a chemical bipropellant rocket engine, but it’s also the most difficult to develop.

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A full-flow engine attempts to squeeze every possible ounce of performance out of the propellant it consumes. The most powerful and efficient chemical rocket engines must consume huge volumes of propellant in a short amount of time without destroying the launch vehicle they’re attached to. To create pressure and spin the pumps that are needed to feed that propellant into their main combustion chamber, engines often burn a small amount of propellant in a separate gas generator or preburner. Gas-generator engines vent that exhaust overboard, reducing efficiency but making for a much simpler design. Staged-combustion engines use preburners to create gas that pumps liquid propellant, and that exhaust gas is eventually injected into the main combustion chamber.

Full-flow staged combustion sets itself apart by having two separate pumps and preburners for oxidizer and fuel. Unlike simpler variants of staged combustion, FFSC engines turn all of their propellant into gas before injecting it into the combustion chamber. That hot gas increases the heat of combustion and the pressure inside the combustion chamber, ensuring that virtually all of the propellant that flows through the engine is combusted and turned into thrust as efficiently as possible. FFSC is exceptionally difficult because of the extra-high temperatures and pressures it requires, as well as the need for an oxygen-rich preburner and pump. In a high-pressure, hot-oxygen environment, virtually anything imaginable – including most metals – will spontaneously combust.

Only complex custom-designed alloys can survive those conditions. SpaceX’s Raptor, the only FFSC engine that has ever flown, is especially difficult because it’s meant to be highly reusable. To be successful, Raptor will have to survive those conditions dozens or even hundreds of times in a row with little to no maintenance in between.

The first booster engine Stoke Space ever attempts to build will be a reusable full-flow staged combustion engine powered by liquid methane and liquid oxygen – essentially a smaller version of SpaceX’s Raptor. Stoke’s booster is otherwise familiar and features deployable landing legs like SpaceX’s Falcon boosters. Lapsa says it will likely also have grid fins.

Reusing the upper stage

In some ways, the upper stage of Stoke’s first rocket is even more ambitious. Powered by hydrogen and oxygen propellant, Stoke has designed a conical capsule-like upper stage with an integral fairing. The upper stage’s propulsion is exotic and unique. A large pump will feed propellant to up to 30 combustion chambers distributed around the rim of its heat shield. The exhaust coming from those 30 chambers will expand and partially push against the upper stage’s equally exotic metallic, liquid-cooled heat shield. That expansion against the heat shield improves the efficiency of the upper stage and means that its engine will technically be an aerospike.

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Stoke has already begun testing a full-scale version of the upper stage’s UFO-like rocket engine with 15 combustion chambers. Since testing began in the second half of 2022, Stoke has completed dozens of static fires. Everyday Astronaut’s tour also revealed that the startup has made significant progress fabricating and assembling its first full-scale upper stage prototype – tanks, nosecone, heat shield, engine, and all.

Reminiscent of SpaceX’s Grasshopper and Starhopper campaigns, Stoke plans to conduct hop tests with that prototype if it makes it through qualification testing. On February 7th, Stoke also revealed that it’s begun testing a crucial component of its full-flow booster engine. All told, Stoke Space is making progress at a remarkable pace and continues to tackle the hardest problems. The startup has also avoided widely publicizing any specific deadlines, instead choosing to let hardware and tangible results speak for themselves. Only time will tell if that approach pays off, but Stoke is off to an exceptionally impressive start in an industry full of impressive rocket startups.

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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SpaceX to launch Starlink V2 satellites on Starship starting 2027

The update was shared by SpaceX President Gwynne Shotwell and Starlink Vice President Mike Nicolls.

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Credit: SpaceX

SpaceX is looking to start launching its next-generation Starlink V2 satellites in mid-2027 using Starship.

The update was shared by SpaceX President Gwynne Shotwell and Starlink Vice President Mike Nicolls during remarks at Mobile World Congress (MWC) in Barcelona, Spain.

“With Starship, we’ll be able to deploy the constellation very quickly,” Nicolls stated. “Our goal is to deploy a constellation capable of providing global and contiguous coverage within six months, and that’s roughly 1,200 satellites.”

Nicolls added that once Starship is operational, it will be capable of launching approximately 50 of the larger, more powerful Starlink satellites at a time, as noted in a Bloomberg News report.

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The initial deployment of roughly 1,200 next-generation satellites is intended to establish global and contiguous coverage. After that phase, SpaceX plans to continue expanding the system to reach “truly global coverage, including the polar regions,” Nicolls said.

Currently, all Starlink satellites are launched on SpaceX’s Falcon 9 rocket. The next-generation fleet will rely on Starship, which remains in development following a series of test flights in 2025. SpaceX is targeting its next Starship test flight, featuring an upgraded version of the rocket, as soon as this month.

Starlink is currently the largest satellite network in orbit, with nearly 10,000 satellites deployed. Bloomberg Intelligence estimates the business could generate approximately $9 billion in revenue for SpaceX in 2026.

Nicolls also confirmed that SpaceX is rebranding its direct-to-cell service as Starlink Mobile.

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The service currently operates with 650 satellites capable of connecting directly to smartphones and has approximately 10 million monthly active users. SpaceX expects that figure to exceed 25 million monthly active users by the end of 2026.

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Elon Musk’s xAI and X to pay off $17.5B debt in full: report

The update was shared initially in a report from Bloomberg News, which cited people reportedly familiar with the matter.

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Credit: xAI

Elon Musk’s social platform X and artificial intelligence startup xAI are reportedly preparing to repay approximately $17.5 billion in outstanding debt in full. 

The update was shared initially in a report from Bloomberg News, which cited people reportedly familiar with the matter.

Morgan Stanley, which arranged the debt financing for both companies, has reportedly informed existing lenders that X and xAI plan to pay back the full amount of the $17.5 billion debt. Bloomberg’s sources did not disclose where the capital for the repayment would be coming from.

X, formerly known as Twitter, assumed roughly $12.5 billion in debt during Musk’s acquisition of the company. xAI separately borrowed about $5 billion through bonds and loans last June. The two firms merged last year under xAI Holdings.

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Bloomberg noted that portions of the debt are relatively recent and may carry early repayment penalties. xAI’s $3 billion in high-yield bonds are expected to be redeemed at 117 cents on the dollar, reflecting a premium since the debt was expected to stay outstanding for at least two years.

X has been servicing tens of millions of dollars in monthly debt payments, while xAI has reportedly been burning approximately $1 billion in cash per month as it invests heavily in data centers, chips, and AI talent. That being said, xAI also concluded a funding round in January, where it raised $20 billion of new equity.

The repayment plans come as Musk consolidates several of his businesses. SpaceX recently acquired xAI, making it a subsidiary as the company explores plans for space-based data centers. The combined entity has been valued at approximately $1.25 trillion.

Bloomberg previously reported that SpaceX is targeting a confidential IPO filing as soon as this month, potentially positioning the private space firm for a public listing later this year. Representatives for Morgan Stanley declined to comment, and X and xAI did not immediately respond to requests for comment.

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Tesla Giga Berlin head calls out Handelsblatt’s claimed 2025 production figures

Andre Thierig, Senior Director of Manufacturing at Giga Berlin, published a detailed post on LinkedIn challenging several points made in the publication’s coverage of the Grünheide facility.

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Credit: Tesla

Tesla Gigafactory Berlin’s plant manager has publicly pushed back against recent reporting by German business publication Handelsblatt, which cited reportedly erroneous data about the factory’s production figures and financial performance.

Andre Thierig, Senior Director of Manufacturing at Giga Berlin, published a detailed post on LinkedIn challenging several points made in the publication’s coverage of the Grünheide facility.

In his LinkedIn post, Thierig called out Handelsblatt’s claim that 149,000 Model Y vehicles were produced at Giga Berlin in 2025. He noted that “the article is simply filled from front to back with false information and claims!

“I have to set the record straight here! In the last article about Tesla in Grünheide, the Handelsblatt speaks e.g. of 149,000 Model Ys built in 2025. WRONG! 

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“In 2025, we again produced over 200,000 vehicles. And this despite the fact that we stopped production in Q1 for the changeover to the new Model Y and then ramped it up again to 5,000 units per week over several weeks,” Thierig wrote. 

He added that production increased each quarter in 2025 compared to the prior quarter and stated that more than 700,000 Model Y units have been produced at Grünheide since manufacturing began in 2022. For the first quarter of 2026, he stated that the factory is planning another production increase compared to the fourth quarter of 2025.

Thierig also questioned Handelsblatt’s reported 0.74% profit margin, writing that how the publication calculated the figure “remains reserved for their secret ‘calculation skills.’”

Beyond production data, Thierig highlighted Tesla’s broader footprint in Germany, stating that the company has invested more than €5 billion in Grünheide since 2020 and created nearly 11,000 permanent, above-tariff jobs. He added that Tesla is currently investing nearly €100 million into battery cell production at the site, which is expected to generate several hundred additional positions.

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In a follow-up comment, Thierig noted that he did communicate with the publication’s editor-in-chief in an effort to “start fresh,” but he was informed that Handelsblatt’s current approach works just fine. 

“Last year, I spoke to a representative of the Handelsblatt editor-in-chief and suggested that we “start anew” again. Handelsblatt turned down this offer on the grounds that their current approach works well for them,” Thierig noted. 

Sönke Iwersen, Head of Investigative Research at Handelsblatt, responded to Thierig’s post, stating that the newspaper’s figures were based on Tesla’s own annual financial statements for the Grünheide entity.

He cited reported 2024 revenue of €7.68 billion, operating profit of €156.8 million, and net income after taxes of €55.6 million. Iwersen also referenced prior public comments from Elon Musk about Cybertruck demand, noting the gap between reported pre-orders and subsequent annual sales figures. 

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He also stated that the works council election eligibility figures Giga Berlin had dropped to 10,703 employees today from 12,415 two years ago.

“As far as production figures are concerned, these are figures from the data service provider Inovev. This is also stated in the article. Please compare this with Elon Musk’s information on demand for the Cybertruck. According to Musk, there were one million pre-orders. In the first year, 39,000 units were sold, in the second year 20,000. How can this be explained? With a million pre-orders?

“You yourself have repeatedly pointed out in recent months that no jobs would be cut in Grünheide because Tesla is different from the competition. Now a new works council is being elected in Grünheide. 10,703 people are eligible to vote. Two years ago, 12,415 people were eligible to vote. So there were exactly 1712 fewer from 2024 to 2026,” Iwersen wrote. 

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