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Falcon 9 B1049 stands at LC-40 ahead of SpaceX's first dedicated Starlink launch. (SpaceX) Falcon 9 B1049 stands at LC-40 ahead of SpaceX's first dedicated Starlink launch. (SpaceX)

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SpaceX reveals new Starlink satellite details 24 hours from launch

Falcon 9 B1049 stands at LC-40 ahead of SpaceX's first dedicated Starlink launch. (SpaceX)

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Less than 24 hours before SpaceX’s first dedicated Starlink mission is scheduled to lift off, the company revealed a handful of new details about the design of the 60 satellites cocooned inside Falcon 9’s fairing.

The Falcon 9 booster assigned to launch the Starlink v0.9 mission – B1049 – has already flown twice before in September 2018 and January 2019 and will likely take part in many additional launches prior to retirement. In support of B1049’s hopeful future, drone ship Of Course I Still Love You (OCISLY) arrived at its recovery location on May 13th, an impressive 620 km (385 mi) downrange relative to the launch’s low target orbit (440 km, 270 mi).

(Extra) smallsats

The combination of a distant booster recovery and a low target orbit can only mean one thing: the Starlink v0.9’s satellite payload is extremely heavy. As it just so happens, that is exactly the case per details included in SpaceX’s official press kit (PDF).

“With a flat-panel design featuring multiple high-throughput antennas and a single solar array, each Starlink satellite weighs approximately 227kg, allowing SpaceX to maximize mass production and take full advantage of Falcon 9’s launch capabilities. To adjust position on orbit, maintain intended altitude, and deorbit, Starlink satellites feature Hall thrusters powered by krypton. Designed and built upon the heritage of Dragon, each spacecraft is equipped with a Startracker navigation system that allows SpaceX to point the satellites with precision. Importantly, Starlink satellites are capable of tracking on-orbit debris and autonomously avoiding collisions. Additionally, 95 percent of all components of this design will quickly burn [up] in Earth’s atmosphere at the end of each satellite’s lifecycle—exceeding all current safety standards—with future iterative designs moving to complete disintegration.”

SpaceX’s first two Starlink prototype satellites deploy from Falcon 9, February 2018. (SpaceX)

First and foremost, an individual satellite mass of around 227 kg (500 lb) is an impressive achievement, nearly halving the mass of the Tintin A/B prototypes SpaceX launched back in February 2018. For context, OneWeb’s essentially finalized satellite design weighs ~150 kg (330 lb) each and relies on a ~1050 kg (2310 lb) adapter capable of carrying ~30 satellites. Accounting for the adapter, that translates to ~180 kg (400 lb) per OneWeb satellite, around 25% lighter than Starlink v0.9 spacecraft.

However, assuming SpaceX has effectively achieved its desired per-satellite throughput of ~20 gigabits per second (Gbps), Starlink v0.9 could provide more than twice the performance of OneWeb’s satellites (PDF). These are still development satellites, however, and don’t carry the laser interlinks that will be standard on the all future spacecraft, likely increasing their mass an additional ~10%.

The second phase of Starlink testing – 60 advanced satellites – in a single fairing. (SpaceX)

Despite the technical unknowns, it can be definitively concluded that SpaceX’s Starlink satellite form factor and packing efficiency are far ahead of anything comparable. Relative to the rockets it competes with, Falcon 9’s fairing is actually on the smaller side, but SpaceX has still managed to fit an incredible 60 fairly high-performance spacecraft inside it with plenty of room to spare. Additionally, SpaceX CEO Elon Musk says that these “flat-panel” Starlink satellites have no real adapter or dispenser, relying instead on their own structure to support the full stack. How each satellite will deploy on orbit is to be determined but it will likely be no less unorthodox than their integrated Borg cube-esque appearance.

That efficiency also means that the Starlink v0.9 is massive. At ~227 kg per satellite, the minimum mass is about 13,800 kg (30,400 lb), easily making it the heaviest payload SpaceX has ever attempted to launch. It’s difficult to exaggerate how ambitious a start this is for the company’s internal satellite development program – Starlink has gone from two rough prototypes to 60 satellites and one of the heaviest communications satellite payloads ever in less than a year and a half.

[Insert Kryptonite joke here]

Beyond their lightweight and space-efficient flat-panel design, the next most notable feature of SpaceX’s Starlink v0.9 satellites is their propulsion system of choice. Not only has SpaceX designed, built, tested, and qualified its own Hall Effect thrusters (HETs) for Starlink, but it has based those thrusters on krypton instead of industry-standard xenon gas propellant.

Based on a cursory review of academic and industry research into the technology, krypton-based Hall effect thrusters can beat xenon’s ISP (chemical efficiency) by 10-15% but produce 15-25% less thrust per a given power input. Additionally, krypton thrusters are also 15-25% less efficient than xenon thrusters, meaning that krypton generally requires significantly more power to match xenon’s thrust. However, the likeliest explanation for SpaceX’s choice of krypton over less exotic options is simple: firm prices are hard to come by for such rare noble gases, but krypton costs at least 5-10 times less than xenon for a given mass.

Hall effect thrusters can typically operate on most noble gases, although they are usually optimized for one or a few options. (Nakles, Hargus, & Corey, 2011)

At the costs SpaceX is targeting ($500k-$1M per satellite), the price of propellant alone (say 25-50 kg) could be a major barrier to satellite affordability – 50 kg of xenon costs at least $100,000, while 50 kg of krypton is more like $10,000-25,000. The more propellant each Starlink satellite can carry, the longer each spacecraft can safely operate, another way to lower the lifetime cost of a satellite megaconstellation.

SpaceX’s dedicated Starlink launch debut is set to lift off no earlier than 10:30pm EDT (02:30 UTC), May 15th. This is not a webcast you want to miss!

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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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Tesla shows what Roadster drivers will see on screen before thruster activation

Tesla’s Roadster video reveals a fighter jet inspired cockpit with a 5,500 PSI thruster gauge.

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The next generation Tesla Roadster’s touchscreen, shown in Tesla’s first official look at the car’s interface. (Credit: Tesla/X)

Tesla has given future owners their clearest look yet at the cockpit of its next generation Roadster. In a 34 second video posted to X on Friday afternoon, the company walked through the car’s touchscreen with a caption: “Inspired by fighter jet cockpits, Roadster’s interface was designed around the pilot.”

The clip opens on a black screen with red graphics and a 3D wireframe of the car, which sits beside the Roadster’s squared off yoke. Tapping parts of the model brings up controls for the rear wing, including low drag and high downforce positions, along with a charging page with a charge limit bar and a small music player. A row of tabs along the bottom reads Home, Vehicle, Listen, Climate and Navigate.

Most of the video is spent in Track Mode. The dashboard shows a live circuit map, a list of session lap times, brake and motor temperatures, and pressure and temperature readouts for each tire. A setup page lets the driver pick Auto, Low Drag, High Downforce or Custom aero modes, adjust aero balance and brake balance, and switch stability and traction control off. Along the bottom, a status bar reads “Thruster · 5,500 PSI” next to a “Boost Ready” indicator.

That gauge ties the software to the hardware Tesla showed off near Waco, Texas on October 15. The Thrust and Rocket versions use cold gas thrusters fed by carbon overwrapped pressure vessels, and Tesla lists 0 to 60 mph times of under 0.9 seconds and under 0.59 seconds for them, as Teslarati detailed in its breakdown of the three Roadster configurations. The base Performance car relies on a fan and ground sealing system for grip, and the aero settings on screen match the active wings and suction setup covered in our look at how the Roadster generates downforce.

The Roadster layout is a departure from the rest of Tesla’s lineup. Instead of a map centered screen, the Roadster puts the car itself at the center of the home page, and Tesla’s Roadster page lists two smaller forward displays alongside the main touchscreen. Tesla has not said whether any of the Track Mode telemetry will make its way to the Model 3 Performance or other vehicles.

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The interface could still change before deliveries. Elon Musk said at the event that Roadster production will begin in 2028, and Tesla says the flagship Rocket version is not approved for public road use. Reservations are open with a $50,000 payment, while Thrust is listed as a limited release and Rocket is invite only.

Those who want to see the car in person will get their first chance this weekend. The Roadster goes on display in the lobby of the Petersen Automotive Museum in Los Angeles from October 24 to 27, according to Sawyer Merritt, the first time the public will be able to view it up close.

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Tesla reveals Optimus Academy, where robots teach themselves

Tesla has begun building production quality Optimus robots in Fremont and revealed its training plan.

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Concept rendering of Tesla Optimus in mass production

Tesla has started building Optimus on the high volume line it set up inside its Fremont factory, and the company says the robots coming off it are the first that meet the bar for a real product. “The bots coming off this line are the first production-quality bots that we have manufactured,” Tesla wrote in its third quarter shareholder letter, adding that it has “proven that the current manufacturing process for Optimus is suitable for a commercial product.”

The line sits in space that built the Model S and Model X until this spring. Tesla cleared the old vehicle line in 46 days, as Teslarati reported in July, to make room for robot production sized for one million units a year. On Wednesday’s earnings call, Elon Musk said most of the equipment for that capacity is already in Fremont, with output set to climb toward roughly 20,000 robots a week as the line ramps.

Musk described the ramp as a classic S curve. “The growth of Optimus is an S curve, but the initial curve is a shallow slope,” he said. The team is now refining the robot’s AI, electromechanical design, reliability and service life, and Musk expects that work to be finished by the end of next year, when Tesla plans to start delivering Optimus to outside companies for dangerous, repetitive and around the clock jobs.

The most interesting part of the call was how Tesla plans to teach the robots. Its cars send real driving data back to the AI team from millions of vehicles, but Optimus has no fleet like that yet. “A big difference with Optimus versus the cars is we don’t have this vast fleet of cars from which we can gather training data,” Musk said. Tesla’s answer is an Optimus Academy, where 10,000 to 20,000 robots will practice a wide range of tasks and feed what they learn into the next version of the model. Every unit off the Fremont line becomes a source of that training data.

Smarter hardware is on the way too. Tesla plans to put its AI5 chip into Optimus next year, and Musk said a new Optimus video should arrive within one or two months showing the robot completing tasks driven by AI rather than preprogrammed motions. He took aim at rival humanoid demos that only run scripted routines, saying those would not hold up in the real world.

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The supply chain is lining up behind the program. In September, Tesla certified Tuopu, Joyson and Sanhua as mass production partners for Optimus components. A far larger Optimus factory is also rising at Giga Texas, where drone footage from Joe Tegtmeyer showed the steel frame nearing completion, and Musk has pegged that plant’s long term target at 10 million robots a year.

Tesla executives also said Optimus production costs are trending toward the expected manufacturing cost of Cybercab, a sign the robot is being engineered for volume from the start. The hands remain the toughest piece of the design, a point Musk also made at the X Takeover event earlier this month, as Teslarati covered at the time, and that is where much of the current engineering effort is focused.

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The Starship moon landing number NASA and Elon Musk can’t agree on

Musk disputes NASA estimate of 22 Starship launches for Moon landing, predicting 6 to 8.

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Concept rendering of SpaceX Starship landing on the moon via Grok

Elon Musk is disputing a new NASA safety panel estimate of how many Starship launches it will take to put astronauts on the Moon, saying the real number will be less than half the panel’s figure.

On Thursday, NASA’s Aerospace Safety Advisory Panel held its quarterly public meeting. Panel member Charlie Precourt, a former NASA astronaut, flagged the fueling process for SpaceX’s lunar lander as a major risk for Artemis IV, the mission planned to land a crew on the Moon in 2028. “We need to keep our eyes on numerous required fuelings for the lander,” Precourt said, according to Ars Technica. “I think the last estimate is around 22 flights.”

Ars Technica’s Eric Berger posted the comment on X, and Musk replied. “That’s way too high,” Musk wrote. “Actual number will be more like 6 to 8.”

The disagreement comes down to a basic problem with sending a ship as large as Starship to the Moon. Starship burns nearly all of its propellant just reaching Earth orbit, so it cannot continue on to the Moon without stopping for a refill. SpaceX’s answer is a gas station in space. First, a Starship that works as a storage tank, called a depot, is launched into orbit. Then a series of tanker Starships launch one at a time, dock with the depot and pump their leftover propellant into it. Once the depot is full, the lunar lander version of Starship launches, docks, fills up and heads for the Moon.

Every tanker trip is its own full rocket launch, which is why the count matters. More launches mean more time, more cost and more chances for something to go wrong before astronauts ever leave Earth. Berger estimated that even if SpaceX reaches twice weekly Starship launches by the end of 2027, filling a depot at the panel’s number would still take roughly three months.

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How many tankers are needed depends mostly on how much propellant each one can carry to orbit and how much is lost along the way. Starship’s fuel and oxygen are stored at extremely cold temperatures, and some of it slowly boils off while waiting in orbit. More is lost in each transfer. NASA appears to be working from what Starship can lift today, while Musk’s range assumes a more capable rocket.

Musk has pushed back on higher counts before. In 2021, after a government document suggested 16 launches, he called that “extremely unlikely” and said eight tankers would be the most required.

Much of the answer depends on hardware SpaceX has not finished flying. As Teslarati noted earlier this year, the company plans to carry out the refueling process with its upgraded V3 Starship, and Precourt described Artemis IV as carrying “a large number of firsts.” He also praised NASA Administrator Jared Isaacman’s team for working to clear obstacles for both SpaceX and Blue Origin, whose Blue Moon lander does not rely on orbital refueling for its first mission.

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