News
Ex-SpaceX engine expert to help design rockets built for launch on world’s largest jet
Stratolaunch, an aerospace company funded by Microsoft-made billionaire Paul Allen to build the world’s largest flightworthy aircraft, has announced a decision to build its own liquid-fueled rockets, to be air-launched from the aforementioned mega-plane.
Targeting an inaugural launch of the first version of the rocket – currently nicknamed “Kraken” – as early as 2022, Stratolaunch has chosen Jeff Thornburg, formerly SpaceX’s Vice President of Propulsion Engineering and the father of the company’s Mars-focused Raptor engine, to lead its foray into in-house rocket propulsion development and manufacturing.
Stratolaunch has confirmed what most people have long speculated: it’s developing its own launch vehicles for its air-launch system, including a reusable space plane that could eventually carry people. pic.twitter.com/nF9lKVe4xk
— Jeff Foust (@jeff_foust) August 20, 2018
But first: building the world’s largest aircraft
Stratolaunch’s first task at hand, however, is to begin flight-testing the largest (hopefully) operational aircraft in history, a prerequisite for the company’s longer-term orbital rocket and spaceplane aspirations. Nicknamed “Roc” after a mythical (and fictional) bird so large it could carry an elephant, the plane certainly lives up to its namesake. Featuring a full six of the same engines that power Boeing’s once-record-breaking 747 airliner and a wingspan that could easily fit three smaller 737 airliners with room to spare, it is genuinely difficult (if not impossible) to successfully convey the sheer scale of Roc outside of witnessing it in person.
Stationed in California’s Mojave Desert, the aircraft’s one and only copy is, for the most part, completed and has spent the brunt of 2018 conducting runway taxi tests, hopefully culminating in an inaugural flight test later this year or early next year. Designed to lift orbital-class rockets weighing as much as 250 metric tons (550,000 lb) to an altitude of at least 9100 meters (30,000 feet), the primary benefit of using aircraft as launch platforms derives from the simple fact that the atmospheric density at 30,000 feet is more than three times less than that at sea level. Similar to aircraft, rocket performance dramatically improves as atmospheric density decreases: less atmosphere means lower drag and pressure.
Rockets that launch from sea-level have to grapple with the difficulties of Earth’s relatively thick atmosphere at that height, with major launch events like “Max-Q” being big concerns almost solely because the dense air exerts major forces on launch vehicles and demands extreme measures like throttling down booster engines (very inefficient) and optimizing structures for aerodynamic efficiency despite the fact that rockets spend very little time operating in a significant atmosphere.
A launch pad without a rocket (sort of)
However, the simple fact of the matter is that billionaire Paul Allen’s colossal aircraft essentially does not have a single air-launched rocket in the world that can properly take advantage of its capabilities. Originally sized and designed with an air-launched version of SpaceX’s Falcon 9 in mind, that relationship folded amicably after roughly a year (2012), at which point SpaceX realized it would need to almost completely redesign a unique variant of Falcon 9. Your author will readily admit that they have admired the insanity of such a massive plane while still severely doubting its practical utility.
Thankfully, it appears that Allen is adamantly opposed to the idea that Stratolaunch is some silly whim to build the world’s largest plane. Rather, he is exceptionally reserved and pragmatic when discussing the aerial launch platform, according to a recent and extensive interview by Wired Magazine’s Steven Levy.
“Allen isn’t one to show exuberance, and when he speaks about the plane he focuses on its future utility. ‘When you see that giant plane, it’s a little nutty,’ he says. ‘And you don’t build it unless you’re very serious, not only about wanting to see the plane fly but to see it fulfill its purpose. Which is getting vehicles in orbit.’ – Paul Allen, 2018
- Stratolaunch’s Roc shown with a triplet of Orbital ATK Pegasus XL rockets. (Vulcan Space)
- Back in 2012, SpaceX briefly entertained the idea of a Falcon 9 variant optimized for air-launch, potentially including crew rating the rocket down the road. (Stratolaunch/Dynetics)
- The Roc is inconceivably vast. (Stratolaunch)
Currently, Orbital ATK’s (now Northrop Grumman Innovation Systems) air-launched Pegasus XL rocket is the only “customer” in the world that can realistically use Stratolaunch as a launch platform, not exactly an impressive or sustainable launch vehicle with a maximum performance of less than 450 kg (~1000 lbs) to low Earth orbit for an incredible ~$40 million per (expendable) flight.
To answer that call and ensure Stratolaunch’s utility, the company reportedly began seriously considering its own in-house expendable and reusable rockets and propulsion systems sometime in 2016, plans that have since grown concrete and been publicly embedded into Stratolaunch’s overarching mission. Nicknamed “Kraken” after the mythical sea monster, the company hopes to develop an initially expendable rocket system capable of launching 3400 – 6000 kg (~7500 – 13250 lbs) into low Earth orbit with single booster and triple booster variants. Further down the line, Stratolaunch is eyeing the design and production of a fully and rapidly reusable orbital spaceplane, potentially including a version that would carry astronauts into space.
- A concept video produced by Stratolaunch shows the Roc launching a Kraken rocket. (Stratolaunch, via Wired)
- A concept video produced by Stratolaunch shows the Roc launching a Kraken rocket. (Stratolaunch, via Wired)
- A concept video produced by Stratolaunch shows the Roc launching a Kraken rocket. (Stratolaunch, via Wired)
- SpaceX’s subscale Raptor engine has completed more than 1200 seconds of testing in less than two years. (SpaceX)
- BFS (circa 2017) shows off its complement of SL and Vacuum Raptor engines. SpaceX is moving back to something similar to this. (SpaceX)
Normally, one might simply roll their eyes at yet another startup touting small(ish) expendable rockets with first launches no earlier than the early 2020s – the market is getting to be absurdly and impossibly overcrowded at this point. However, Stratolaunch differs for one fundamental and reason: they have placed ex-SpaceX propulsion executive and expert Jeff Thornburg at the helm of the company’s freshly public rocket propulsion wing. While at SpaceX, Mr. Thornburg spent all but one of his five years with the company (2011-2015) single-mindedly focused on the development and engineering of all aspects of the Raptor rocket engine, a next-generation propulsion system designed to enable SpaceX’s sustainable colonization of Mars.
Raptor is an exceptional rocket engine thanks in no small part to Thornburg’s brilliance as a propulsion engineer, and that same brilliance and half-decade of experience at the most successful rocket startup in existence could ultimately prove a massive boon for Stratolaunch’s otherwise interesting but unexceptional expendable rocket concepts.
Put simply, under Jeff Thornburg’s direction and with access to founder Paul Allen’s considerable wealth, Stratolaunch is undoubtedly worth keeping a close eye in the future, both far and near.
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’s xAI closes upsized $20B Series E funding round
xAI announced the investment round in a post on its official website.
xAI has closed an upsized $20 billion Series E funding round, exceeding the initial $15 billion target to fuel rapid infrastructure scaling and AI product development.
xAI announced the investment round in a post on its official website.
A $20 billion Series E round
As noted by the artificial intelligence startup in its post, the Series E funding round attracted a diverse group of investors, including Valor Equity Partners, Stepstone Group, Fidelity Management & Research Company, Qatar Investment Authority, MGX, and Baron Capital Group, among others.
Strategic partners NVIDIA and Cisco Investments also continued support for building the world’s largest GPU clusters.
As xAI stated, “This financing will accelerate our world-leading infrastructure buildout, enable the rapid development and deployment of transformative AI products reaching billions of users, and fuel groundbreaking research advancing xAI’s core mission: Understanding the Universe.”
xAI’s core mission
Th Series E funding builds on xAI’s previous rounds, powering Grok advancements and massive compute expansions like the Memphis supercluster. The upsized demand reflects growing recognition of xAI’s potential in frontier AI.
xAI also highlighted several of its breakthroughs in 2025, from the buildout of Colossus I and II, which ended with over 1 million H100 GPU equivalents, and the rollout of the Grok 4 Series, Grok Voice, and Grok Imagine, among others. The company also confirmed that work is already underway to train the flagship large language model’s next iteration, Grok 5.
“Looking ahead, Grok 5 is currently in training, and we are focused on launching innovative new consumer and enterprise products that harness the power of Grok, Colossus, and 𝕏 to transform how we live, work, and play,” xAI wrote.
Investor's Corner
Tesla gets price target bump, citing growing lead in self-driving
Tesla (NASDAQ: TSLA) stock received a price target update from Pierre Ferragu of Wall Street firm New Street Research, citing the company’s growing lead in self-driving and autonomy.
On Tuesday, Ferragu bumped his price target from $520 to $600, stating that the consensus from the Consumer Electronics Show in Las Vegas was that Tesla’s lead in autonomy has been sustained, is growing, and sits at a multiple-year lead over its competitors.
CES 2026 validates Tesla’s FSD strategy, but there’s a big lag for rivals: analyst
“The signal from Vegas is loud and clear,” the analyst writes. “The industry isn’t catching up to Tesla; it is actively validating Tesla’s strategy…just with a 12-year lag.”
The note shows that the company’s prowess in vehicle autonomy is being solidified by lagging competitors that claim to have the best method. The only problem is that Tesla’s Vision-based approach, which it adopted back in 2022 with the Model 3 and Model Y initially, has been proven to be more effective than competitors’ approach, which utilizes other technology, such as LiDAR and sensors.
Currently, Tesla shares are sitting at around $433, as the company’s stock price closed at $432.96 on Tuesday afternoon.
Ferragu’s consensus on Tesla shares echoes that of other Wall Street analysts who are bullish on the company’s stock and position within the AI, autonomy, and robotics sector.
Dan Ives of Wedbush wrote in a note in mid-December that he anticipates Tesla having a massive 2026, and could reach a $3 trillion valuation this year, especially with the “AI chapter” taking hold of the narrative at the company.
Ives also said that the big step in the right direction for Tesla will be initiating production of the Cybercab, as well as expanding on the Robotaxi program through the next 12 months:
“…as full-scale volume production begins with the autonomous and robotics roadmap…The company has started to test the all-important Cybercab in Austin over the past few weeks, which is an incremental step towards launching in 2026 with important volume production of Cybercabs starting in April/May, which remains the golden goose in unlocking TSLA’s AI valuation.”
Tesla analyst breaks down delivery report: ‘A step in the right direction’
Tesla has transitioned from an automaker to a full-fledged AI company, and its Robotaxi and Cybercab programs, fueled by the Full Self-Driving suite, are leading the charge moving forward. In 2026, there are major goals the company has outlined. The first is removing Safety Drivers from vehicles in Austin, Texas, one of the areas where it operates a ride-hailing service within the U.S.
Ultimately, Tesla will aim to launch a Level 5 autonomy suite to the public in the coming years.
Elon Musk
Elon Musk’s Biggest Revelations on AI, Robots, and the Future of Work from the Moonshots Podcast
Elon Musk’s appearance on the Moonshots with Peter Diamandis podcast was packed with bold predictions, candid admissions, and surprising tech insights. The nearly three-hour conversation covered everything from artificial intelligence to humanoid robots, geopolitics, and the future of work. Here are the top 10 most intriguing takeaways:
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Aggressive AGI Timeline Predictions
Musk offered a detailed view on when artificial general intelligence (AGI) could emerge, suggesting it may arrive sooner than many expect, emphasizing both transformative potential and risks.
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U.S. vs. China in the AI Race
He discussed the strategic competition between the United States and China over AI development, noting that geopolitical dynamics will shape how and who leads in the next decades.
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Future of Job Markets
Musk touched on how AI and automation could reshape employment, predicting massive boosts in productivity alongside potential disruptions in traditional work structures.
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Clean Energy Transition
A recurring theme was the role of clean energy in future economies, with Musk reiterating the importance of scaling sustainable power generation and storage.
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Humanoid Robots Are Coming
On the podcast, Musk elaborated on Tesla’s work on humanoid robots, hinting at timelines and applications that go beyond factories to general-purpose assistance.
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Tesla Roadster “Last Human-Driven Car”
Outside the core discussion topics, Musk teased features of the upcoming Tesla Roadster — calling it “the best of the last of the human-driven cars” and suggesting safety won’t be its main selling point.
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The Role of AI in Clean Energy and Robotics
Linking AI to both energy optimization and robotics, Musk explained how smarter systems could accelerate decarbonization and task automation across industries.
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U.S. Innovation Leadership
Musk argued that maintaining American leadership in key tech sectors like AI, space, and robotics should be a national priority, with thoughtful policy and investment.
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Job Creation vs. Job Elimination
While acknowledging automation’s disruptive effects, he also outlined scenarios where new industries and opportunities could emerge, particularly in AI, space, and advanced manufacturing.
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Long-Term Vision for Humanity
Throughout the conversation, Musk revisited his long-term philosophical views — including a belief in humanity’s responsibility to become a multi-planetary and technologically empowered species.
Whether you agree with Musk’s optimism or not, the podcast offers a window into the thinking of one of the most influential figures in tech today, in and why his visions continue to spark debate and inspiration.







