SpaceX
SpaceX’s Starship hopper spotted with trio of dual-bell Raptor engines
Following a brief ‘hop’ (via crane) off of a concrete build stand, the aft section of SpaceX’s first full-scale Starship hopper (Starhopper?) revealed that SpaceX technicians have already installed what appear to be three real Raptor engines, presumably the first time the propulsion system has ever been mounted to something that might eventually fly.
For a number of reasons, there is a strong chance that these Raptors are actually just boilerplate placeholders standing in as structural guides for the real deal some months down the line. On the other hand, there are also a number of reasons to assume that these apparent engines are indeed real Raptors.
Star ship hopper might be a bit bigger than we thought and with the crane placements over the nose end of the vehicle. This could suggest, @SpaceX are planning to move the segment elsewhere perhaps to the welding stand? We will have to wait and see. (Austin Barnard📸) #2019🚀 pic.twitter.com/kn8hhUPWCU
— Austin Barnard🚀 (@austinbarnard45) January 1, 2019
Despite an already shocking series of rapid-fire developments in the South Texas Starhopper saga, the abrupt appearance of what appears to be three Raptor engines – mirroring CEO Elon Musk’s recent statement that the test vehicle would sport three Raptors – is by far the most unexpected moment yet for the prototype Starship. Purportedly a full-scale prototype of BFR’s upper stage/spaceship (now known as Starship), Musk indicated over the last two weeks that the hopper has been designed to perform a number of hop tests in which the craft’s three Raptors would power it to a range of (relatively low) altitudes above Boca Chica, Texas.
According to a recent FCC filing related to this test program, SpaceX is currently seeking a license for Starship hop tests that will not exceed 5 km (3.1 mi) in altitude and/or 6 minutes in duration. There is admittedly nothing mentioned about the maximum allowed velocity during those tests, but – much like Blue Origin performs supersonic tests of New Shepard in Cape Horn, Texas – SpaceX will likely seek and be granted permission to break the sound barrier during those hypothetical tests. Nevertheless, a 5km ceiling is a fairly significant cap on the range of performance Starhopper will be able to test – accelerating vertically at 2Gs, Starhopper could travel from sea level to 5km in less than 30 seconds while reaching speeds no higher than Mach 1-1.5.
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- SpaceX technicians and engineers are continuing to work at a breakneck pace on Starhopper. (NASASpaceflight – bocachicagal)
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- At this rate, the hopper will likely wind up around 40m (130 feet) tall. (NASASpaceflight – bocachicagal)
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- A close examination of these three engine-like protrusions suggests a level of fit and finish far exceeding a boilerplate stand-in. (NASASpaceflight – bocachicagal)
Combined with the apparent fact that this Starhopper’s fins seem unlikely to ever actuate (i.e. no aerodynamic control surfaces), it’s probable that this ad hoc prototype is only meant to perform a very limited range of hop tests, perhaps as basic as ironing out the kinks of operating a trio of gimballed Raptors and ensuring that they can safely and reliably launch, hover, and land a very large Starship-shaped mass simulator. Falcon 9’s Grasshopper and F9R reusability testbeds performed a very similar task some five years ago, offering SpaceX engineers the opportunity to optimize software and hardware needed to reliably recover real orbital-class rockets after launch. Although Falcon 9 has nine gimballed Merlin 1D engines, SpaceX has long sided with the sole center Merlin as the dedicated landing engine and has only briefly experimented with triple-Merlin landing burns.
Dual-expansion whaaaaat?
According to Musk, Raptor – an advanced liquid methane and oxygen engine with a uniquely efficient propulsion cycle – was expected to produce an impressive ~2000 kN (200 ton, 450K lbf) of thrust in its finished form as of September 2018. However, Musk also mentioned in a late-2017 Reddit AMA that SpaceX engineers were modifying the ship’s design to ensure engine-out reliability during all regimes of flight, landing in particular. To accomplish this feat with an engine as powerful as Raptor, two or three Raptors – capable of producing as much as 600 tons of thrust total – would need to reliably throttle as low as 25%, assuming a landing mass of around 150t. To allow a nearly empty ship (~100t) to still reliably land with three Raptors ignited, the engines would need to be able to throttle to 20% or less.
Known as deep throttling in rocketry, ensuring stable combustion and thrust at 20% (let alone 40%) throttle is an extraordinarily challenging feat, often subjecting engines to forces that can literally tear non-optimized hardware apart. To achieve such a deep throttle capability without excessively disrupting the engine’s design, SpaceX appears to have potentially sided with less efficient but extremely simple alternative, known as a dual-bell (or dual-expansion) rocket nozzle. A 1999 Rocketdyne paper concisely explained the primary draws of such a nozzle:
“The [altitude-compensating] dual-bell nozzle offers a unique combination of performance, simplicity, low weight, and ease of cooling” – Horn & Fisher, 1999
Exactly
— Elon Musk (@elonmusk) December 27, 2018
Given that SpaceX has decided to delay the introduction and certification of a vacuum-optimized Raptor engine, choosing to instead use the same Raptor on both BFR stages, something like a dual-bell nozzle would be one of the best possible ways for the company to retain some of the efficiency benefits of a vacuum engine while also drastically improving design simplicity, ease of manufacturing, and cutting development time. Aside from offering efficiency gains by way of altitude compensation, a dual-bell nozzle also happens to enable a given engine to operate a much wider throttle range by mitigating problems with flow separation and instability.
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- A gif of Raptor throttling over the course of a 90+ second static-fire test in McGregor, Texas. (SpaceX)
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- Note that Merlin 1D and prior Raptor prototypes both feature traditional single nozzles. (Pauline Acalin)
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- An overview of dual-bell and deflection nozzles. Raptor appears to have now graduated to the former style. (Johan Steelant, 2011)
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- Starhopper’s Raptors feature a very distinct seam and second curve, indicative of a dual-bell nozzle. (NASASpaceflight /u/bocachicagal)
For Starhopper and Starship, both aspects are an undeniable net-gain and it’s entirely possible that these dual-bell nozzles – if successfully demonstrated – could find their way onto Falcon 9 and Falcon Heavy to further boost their booster performance and efficiency.
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Elon Musk
SpaceX Board has set a Mars bonus for Elon Musk
SpaceX has given Elon Musk the goal to put one million people on Mars.
SpaceX’s board approved a compensation plan for Elon Musk that ties his pay directly to colonizing Mars and building data centers in outer space. The details surfaced this week after Reuters reviewed SpaceX’s confidential registration statement filed with the Securities and Exchange Commission, making it one of the first concrete looks inside the company’s financials ahead of a public offering.
The pay package will reportedly award Musk 200 million super-voting restricted shares if the company hits a market valuation milestone, with the most ambitious targets going further. To unlock the full award, SpaceX would need to reach a $7.5 trillion valuation and help establish a permanent human settlement on Mars with at least one million residents. Additional incentives are tied to developing space-based computing infrastructure capable of delivering at least 100 terawatts of processing power.
SpaceX wins its first MARS contract but it comes with a catch
Long before SpaceX filed anything with the SEC, Elon Musk had already spent years framing Mars colonization as an insurance policy against human extinction. The philosophy traces back to at least 2001, when Musk first began researching Mars missions independently, before SpaceX even existed. By 2002 he had founded the company with Mars as the stated long-term goal.
In a 2017 presentation at the International Astronautical Congress, Musk outlined the specific vision that still underpins SpaceX’s architecture today. He described a self-sustaining city on Mars requiring roughly one million people to become viable, the same number now written into his compensation package.
SpaceX’s Starship, still in active development, was designed from the ground up to support the eventual colonization of Mars. Musk has stated publicly that getting the cost per ton to Mars below $100,000 is necessary to make mass migration economically feasible. Everything from Starship’s payload capacity to its full reusability targets flows from that single constraint. One can say that Musk’s latest compensation package has put a formal valuation on Mars for the first time.
SpaceX is targeting an IPO around June 28, Musk’s birthday, at a valuation of approximately $1.75 trillion. Between the Mars rover contract, the Golden Dome software group, Space Force satellite launches, and now a pay structure built around interplanetary colonization, SpaceX has become the single most consequential contractor in American space and defense. The IPO will put a public price tag on all of it for the first time.
News
UPDATE: SpaceX’s Falcon Heavy that launched a Tesla into space is back on a mission
SpaceX Falcon Heavy returns after 18 months away to deliver a satellite that only it could carry.
UPDATE: 10:29 a.m. et: SpaceX is standing down from today’s Falcon Heavy launch of the ViaSat-3 F3 mission due to unfavorable weather. A new target date will be shared once confirmed.
After an 18-month absence, SpaceX’s Falcon Heavy is returning to mission on Monday morning when it’s scheduled to lift off from Launch Complex 39A at Kennedy Space Center at 10:21 a.m. EDT.
The mission is called ViaSat-3 F3, and the heavy satellite payload needs to reach geostationary orbit, sitting 22,236 miles above Earth where its speed matches the planet’s rotation. Getting a satellite that heavy to that altitude demands more thrust than a single-core Falcon 9 can deliver.
This marks the Falcon Heavy’s 12th flight overall since its debut in February 2018, and its first since NASA’s Europa Clipper mission in October 2024.
Arguably, the most exciting element for spectators will be watching the booster recoveries in action when the two side boosters, B1072 and B1075, will attempt simultaneous landings at Landing Zone 2 and the newer Landing Zone 40 at Cape Canaveral Space Force Station, while the center core will be expended over the ocean.
SpaceX wins its first MARS contract but it comes with a catch
Following satellite deployment, expected roughly five hours after launch, ViaSat-3 F3 will spend several months traveling to its final orbital slot before undergoing in-orbit testing, with service entry expected by late summer 2026
As Teslarati reported, NASA awarded SpaceX a $175.7 million contract on April 16, 2026, to launch the ESA Rosalind Franklin Mars rover aboard a Falcon Heavy no earlier than late 2028, which would mark the first time SpaceX has ever sent a payload to Mars. That contract came on top of an already deep pipeline that includes the Roman Space Telescope, the Dragonfly Saturn mission, and multiple national security payloads.
SpaceX executed 165 missions in 2025 and now accounts for approximately 85% of all global orbital launches. With Starlink surpassing 10 million subscribers and an IPO targeting a $1.75 trillion valuation still ahead, Monday’s launch is one more data point in a company that has quietly become the backbone of both commercial and government space access worldwide.
Elon Musk
The FCC just said ‘No’ to SpaceX for now
SpaceX is fighting the FCC for spectrum that could put satellites inside every smartphone.
SpaceX was dealt a new setback on April 23, 2006 by the Federal Communications Commission (FCC) after the U.S. government agency dismissed the company’s petition to access a Mobile Satellite Service spectrum that would allow direct-to-device (D2D) capabilities.
The FCC regulates communications by radio, television, wire, and cable, which also includes regulating D2D technology that lets your existing smartphone connect directly to a satellite orbiting Earth, the same way it would connect to a cell tower.
Elon Musk’s SpaceX has been building toward this through its Starlink Mobile service, formerly called Direct-to-Cell, in partnership with T-Mobile. The service officially launched on July 23, 2025, starting with messaging and expanding to broadband data in October of that year.
T-Mobile Starlink Pricing Announced – Early Adopters Get Exclusive Discount
It’s worth noting that SpaceX is not alone in this race. AT&T and Verizon have their own satellite texting deals with AST SpaceMobile, while Verizon separately offers free satellite texting through Skylo on newer phones.
The regulatory foundation for all of this dates to March 14, 2024, when the FCC adopted the world’s first framework for what it called Supplemental Coverage from Space, allowing satellite operators to lease spectrum from terrestrial carriers and fill gaps in their coverage. On November 26, 2024, the FCC granted SpaceX the first-ever authorization under that framework, approving its partnership with T-Mobile to provide service in specific frequency bands. SpaceX then went further, completing a roughly $17 billion acquisition of wireless spectrum from EchoStar, which gave it the ability to negotiate with global carriers more independently.
Starlink’s EchoStar spectrum deal could bring 5G coverage anywhere
This recent ruling by the FCC blocked SpaceX from going further, protecting incumbent spectrum holders like Globalstar and Iridium. But the market momentum is already in motion. As Teslarati reported, SpaceX is targeting peak speeds of 150 Mbps per user for its next generation Direct-to-Cell service, compared to roughly 4 Mbps today, which would bring satellite connectivity close to standard carrier performance.
With a reported IPO targeting a $1.75 trillion valuation on the horizon, each spectrum fight, carrier deal, and regulatory win or loss now carries weight beyond just connectivity. SpaceX is quietly becoming the infrastructure layer underneath the phones of millions of people, and the FCC’s next move will help determine how much further that reach extends.
FCC Satellite Rule Makings can be found here.
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