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How SpaceX is able to achieve its amazing rocket landing accuracy
After SpaceX’s successful and uniquely exciting launch of Taiwan’s Formosat-5 remote sensing satellite, Elon Musk took to Twitter to reveal some fascinating details about the launch and recovery of the Falcon 9 first stage.
Unabashedly technical, the details Musk revealed demonstrate the truly incredible accuracy of Falcon 9’s recovery, honed over 20 landing attempts and numerous modifications to the launch vehicle. The accuracy is best understood within the context of Falcon 9’s scale and the general scope of orbital rocketry.
Touchdown:
Vertical Velocity (m/s): -1.47
Lateral Velocity (m/s): -0.15
Tilt (deg): 0.40
Lateral position: 0.7m from target center— Elon Musk (@elonmusk) August 25, 2017
The first stage of Falcon 9 Full Thrust, currently the active version of Falcon 9, stands 140 feet tall and 12 feet in diameter. If you can, for a moment, picture a 737 airliner, the plane most people have likely flown aboard on domestic flights. The first stage of Falcon 9 is the same length or greater and the same diameter as Boeing’s workhorse airliner. If you are now imagining a 737 landing on its tail aboard an ocean-going barge, that is a great start. The most common version of the 737, the -800, has an empty weight of 91,000 lb, while Falcon 9’s empty first stage is a bit more than half as heavy. With a full load of fuel, Falcon 9 S1 (first stage) weighs nearly three times as much as the 737-800. A single Merlin 1D engine out of Falcon 9’s namesake nine rocket engines has nearly ten times the thrust of the airliner. In short, Falcon 9’s first stage is massive, both extremely light and extremely heavy, and has a mind-boggling amount of thrust.
Falcon 9’s ability to land as accurately as it does is due to a combination of multiple technologies and vehicle modifications. Most visible are S1’s cold gas maneuvering thrusters and aluminum or titanium grid fins, both of which are designed to provide some level of control authority and maneuverability to the first stage during its trip within and without Earth’s atmosphere. At the peak of its trips, the first stage is often completely outside of the vast majority of the atmosphere, meaning that aerodynamic forces are no longer relevant or useful for the vehicle. This is where the cold gas thrusters come in: by carrying their reaction mass with them (the gas), Falcon 9 can maneuver outside of the atmosphere. Once the stage descends into thicker atmospheric conditions, the grid fins deploy and are used like wings to guide the stage down to its landing location, be that on land or at sea. While the gas thrusters lose a lot of their utility once in the atmosphere, they can still be used to add a small amount of control authority when needed. They were famously seen fighting a futile battle to save a first stage aboard OCISLY in 2015.
With this in mind, we can take a closer look at Musk’s technical details. First off, we have a photo of the landed booster, Falcon 9 1038, clearly almost dead center on the droneship Just Read The Instructions. More specifically, Musk reports that 1038 landed less than a single meter off the center of the target, and it landed with less than a single meter per second of latent velocity. The first stage thus managed both a soft and deadly accurate landing after traveling to a height of 150 miles – well into what is technically “space” – at a maximum speed of 1.5 miles per second. Without delving further into the details, this is best summarized as “insanely fast”, and is a bit faster than the X-15 rocketplane’s fastest recorded speed. To better put this into context, Falcon 9 1038 traveled to an altitude of 240,000 meters at a top speed of 2,400 meters per second, turned around, and landed on an autonomous barge about two feet off of its optimal target. It is truly difficult to describe how impressive that kind of accuracy is.
The hypersonic X-15 and Falcon 9 S1, with a 737-800 on the right. All vehicles are to scale. (Wikipedia, SpaceX)
Mr. Musk nevertheless did not let 1038 steal all the fanfare, and revealed that the first stage responsible for launching BulgariaSat-1, 1029, had the honor of being the fastest first stage yet, clocking in at at a truly staggering Mach 7.9, or 2,700 meters per second. That speedy mission marked the stage’s second flight and was SpaceX’s second successful reuse of a Falcon 9. Indicative of the intense speed and heat the core experienced, one of the vehicle’s grid fins was noted to have almost completely melted through. Aluminum’s melting point begins at 1,221°F.
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- The central aluminum grid fin of 1029 features a dramatic lack of several vanes, likely melted off during the intense heat of reentry. Expending older boosters is likely helping SpaceX learn how to preserve Block 5 rockets for multiple high-energy missions. (Reddit, u/thedubya22)
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- SpaceX will move to titanium grid fins in the future, first trialed during 1036’s launch of Iridium-2. (SpaceX)
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Tesla Sweden’s port deal sparks political clash in Trelleborg
The extension of Tesla’s lease has drawn criticism from the local Social Democratic opposition.
Tesla Sweden’s lease agreement at the Port of Trelleborg has triggered a political dispute, with local leaders divided over whether the municipally owned port should continue renting space to the electric vehicle maker amidst its ongoing conflict with the IF Metall union.
Tesla Sweden’s recently extended contract with the Port of Trelleborg has triggered calls for greater political oversight of future agreements.
Tesla has used the Port of Trelleborg to import vehicles into Sweden amid a blockade by the Transport Workers’ Union, as noted in a report from Dagens Arbete (DA). By routing cars via trucks on passenger ferries, the company has maintained deliveries despite the labor dispute. Vehicles have also been stored and prepared in facilities leased from the municipal port company.
The extension of Tesla’s lease has drawn criticism from the local Social Democratic opposition. Initially, the Port of Trelleborg hinted that it would not enter into new agreements with Tesla, but it eventually opted to renew its existing contract with the EV maker anyway.
Lennart Höckert, an opposition councilor, described the port’s decision as a “betrayal of the Swedish model,” arguing that a municipally owned entity should not appear to side with one party in an active labor dispute.
“If you want to protect the Swedish model, you shouldn’t get involved in a conflict and help one of the parties. When you as a company do this, it means that you are actually taking a position and making things worse in an already ongoing conflict,” Höckert said.
He added that the party now wants politicians to review and approve future rental agreements involving municipal properties at the port.
The proposal has been sharply criticized by Mathias Andersson of the Sweden Democrats, who chairs the municipal board. In comments to local media, Andersson described the Social Democrats’ approach as “Kim Jong Un-style,” arguing that political leaders should not micromanage a company governed by its own board.
“I believe that the port should be run like any other business,” Andersson said. He also noted that operational decisions fall under the authority of the Port of Trelleborg’s board instead of elected officials.
Elon Musk
Elon Musk’s X sees outage on Monday as users report issues
Monday’s outage follows a similar issue that befell the social media platform in mid-January.
X experienced an outage on Monday morning, with tens of thousands of users reporting that the platform failed to load across both desktop and mobile. The disruption began around 8:02 a.m. ET, as per Downdetector data, and quickly escalated in the U.S. and U.K.
Monday’s outage follows a similar issue that befell the social media platform in mid-January.
Shortly after 8 a.m. ET, Downdetector showed a sharp rise in incident reports. At one point, U.S. complaints exceeded 40,000, while U.K. reports climbed past 6,000. Earlier in the outage, filings had already crossed 11,000 in the U.S. and 3,300 in the U.K., as noted in a TechRadar report. X users in other locations, such as the Philippines and Costa Rica, also reported similar issues.
Users attempting to access X were met with a “something went wrong” message. Feeds did not refresh, posts failed to appear, and both the social media platform’s app and web versions appeared affected by the issue. The outage struck during peak weekday usage, amplifying its visibility across regions worldwide.
X has not issued an official explanation for the latest outage or confirmed what caused the service disruption. The scale of complaints drew comparisons to the platform’s major outage in November 2025, which resulted in users being met with “Internal server error / Error code 500” messages, as well as Cloudflare-related error notices.
The incident also comes just weeks after X experienced a similar downtime in mid-January. That outage seemed more notable, however, with more than 100,000 users reporting issues with the social media platform on Downdetector.
Elon Musk
New details emerge on The Boring Company’s Universal tunnel plans
The materials outline staffing, construction timelines, tunnel configuration, and operational details that were not previously public.
Newly released bidding documents have shed light on how Elon Musk’s Boring Company plans to connect Universal Orlando Resort’s north campus to Universal Epic Universe.
The materials outline staffing, construction timelines, tunnel configuration, and operational details that were not previously public about the planned Loop system.
The Shingle Creek Transit & Utility Community Development District voted Feb. 11 to begin contract negotiations with The Boring Company after ranking it the top bidder for the Universal Orlando transport project. Now, evaluation documents obtained by local news media reveal how the company intends to execute the project, according to Attraction Insight.
The proposal describes a twin-tunnel configuration, with one tunnel in each direction. It also noted that permitting, design, and construction could take roughly a year and a half once approvals are secured. The company indicated it could deploy multiple tunnel boring machines and install temporary support infrastructure, including muck storage pits and stormwater systems, during construction.
Bid documents list eight internal specialists assigned to the project, including tunnel engineers, structural engineers, and tunnel boring machine experts. Six subcontractors would handle fire protection, communications, soil treatment, and concrete work.
The company stated it “has the necessary internally produced tunneling equipment and personnel immediately available to complete this project for the district as quickly as permits and approvals can be obtained.”
Operationally, the system would mirror the company’s Las Vegas Loop model, using Tesla vehicles to provide point-to-point transport rather than fixed-route buses. The proposal frames the concept as “on-demand, express transportation,” with vehicles dispatched as needed and capacity adjustable in real time.
Stations could be built underground or above ground with ramp access into tunnels. The documents also referenced potential future integration of a configurable Robovan for passengers and cargo, though capacity projections for the Orlando tunnels have not yet been disclosed.
The proposal states that the Loop can integrate “easily into environmentally sensitive areas,” but it does not provide detailed mitigation plans for Central Florida’s high water table and limestone geology, which is susceptible to sinkholes. The company has stated that it intends to hire an Orlando-based geotechnical firm to evaluate soil conditions.
Tesla Sweden’s port deal sparks political clash in Trelleborg
Elon Musk’s X sees outage on Monday as users report issues
