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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’s Roadster appearance at SpaceX has merger watchers talking

Tesla’s next generation Roadster was spotted at SpaceX’s Hawthorne headquarters, two weeks after its unveiling.

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The Roadster’s rear wing, one of the aerodynamic elements Tesla pairs with a fan-based downforce system. (Image: Tesla)

Tesla’s next generation Roadster turned up at SpaceX’s headquarters in Hawthorne, California on Wednesday, less than two weeks after the car flew off a ramp at its unveiling in Texas.

Photos shared on X by SpaceX Engineer (@DeannaRiceSPCX) show the new Roadster parked outdoors beside the famed Falcon 9 that stands outside company headquarters at the corner of Crenshaw Boulevard and Jack Northrop Avenue. Rocket B1019 was the first orbital-class booster ever to land after a launch on December 21, 2015 after it sent 11 Orbcomm satellites to orbit and then flew back to Landing Zone 1 at Cape Canaveral, which would be the first landing in what became SpaceX’s reusable rocket program. SpaceX chose not to fly it again. After a test fire in Florida, the booster was shipped to Hawthorne and raised upright as a permanent monument in August 2016, as Teslarati reported at the time. Putting the Roadster, which flies on SpaceX cold gas thrusters, next to the rocket that started SpaceX’s landings is symbolic in itself.

The Thrust and Rocket versions of the Roadster use cold gas thrusters fed by composite overwrapped pressure vessels, the same type of tank SpaceX flies on Falcon 9, and Elon Musk described the car as the work of Tesla and SpaceX engineers working together. Tesla lists 0 to 60 mph in under 0.9 seconds for Thrust and under 0.59 seconds for Rocket, while the base Performance model relies on a fan and ground sealing system for grip, as Teslarati detailed in its breakdown of the three Roadster configurations.

Tesla has kept the car in the spotlight since the October 15 event near Waco. Last week, the company posted a video of the Roadster’s fighter jet inspired cockpit, including a Track Mode screen with a “Thruster · 5,500 PSI” readout, which we covered in our look at the Roadster’s center display. Musk also said owners will be able to ask the car to perform the stunts autonomously, and promised a looping track at Tesla’s Texas headquarters.

The visit comes as special committees at Tesla and SpaceX weigh a possible merger, a step Musk confirmed on SpaceX’s third quarter earnings call. The Roadster, built on SpaceX hardware, has become one of the clearest examples of the two companies already building products together.

Musk said at the unveiling that Roadster production will begin in 2028. Reservations are open with a $50,000 payment, Thrust is listed as a limited release and Rocket is invite only. Tesla says the car is not approved for public road use.

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Verizon, AT&T and T-Mobile are trying to shut Starlink out before FCC vote

AT&T, Verizon and T-Mobile want 290 MHz cut from an FCC satellite plan before Thursday.

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Starlink D2D direct to device vs Verizon, AT&T (Concept render by Grok)

AT&T, Verizon and T-Mobile are asking the Federal Communications Commission to pull nearly 300 MHz of spectrum out of a proposal that would let satellite companies like SpaceX offer cell service directly to ordinary phones. The request lands one day before the agency votes on it.

The FCC will vote Thursday, October 29, on a notice of proposed rulemaking that would make an additional 482 MHz available for direct to device service, expanding the number of eligible bands from five to 13, according to the FCC fact sheet. It would also scrap the rule requiring a satellite operator to lease spectrum from carriers, replacing it with a certification that the operator has coexistence agreements in place or holds the terrestrial license itself.

That second path matters for SpaceX. As Teslarati reported earlier this month, SpaceX agreed to buy Grain Management’s nationwide 800 MHz portfolio to turn Starlink Mobile into a full US carrier, adding to the spectrum it already bought from EchoStar.

The carriers want two bands removed, 2.5 GHz and 3.45 GHz, which make up 290 MHz of the 482 MHz on the table. Through industry group CTIA, they argued that about 300 million users depend on those bands and that satellite operations in them are not technically feasible. T-Mobile, which calls 2.5 GHz the foundation of its Ultra Capacity 5G network, said in its own filing that satellite interference could wipe out up to 96% of a cell site’s uplink coverage area and cut uplink speeds by 88% to 99%.

Executives from all three carriers met with FCC staff on October 20, and T-Mobile CEO Srini Gopalan met separately with FCC Chairman Brendan Carr. T-Mobile’s role stands out because it is still SpaceX’s US launch partner for Starlink Mobile. The three carriers have also teamed up on their own satellite joint venture to pool spectrum, a move widely seen as a response to Starlink.

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SpaceX is asking for the opposite. In an October 23 filing after meetings with FCC staff and commissioners’ offices, the company asked regulators to add the 902 to 928 MHz band to the proposal. “Doing so now saves time later,” SpaceX wrote. The company also asked the FCC to modernize interference rules and align satellite deployment requirements with those for terrestrial cell networks, saying the goal is to let satellite and ground networks work together so Americans stay connected wherever they are.

The carriers have not been shy about how they view SpaceX as a competitor. On Verizon’s third quarter earnings call Monday, its chief executive said Starlink Mobile “just can’t compete with a terrestrial network” and estimated SpaceX would need four to six years and $300 billion to $500 billion to build a full US carrier network.

Thursday’s vote will not settle which bands survive. Adopting the notice opens a public comment period, with final rules to come later in the proceeding. The FCC already considered and rejected 2.5 GHz for satellite coverage once, in 2024. SpaceX also is not the only satellite player watching: the FCC approved Amazon’s $11.6 billion acquisition of Globalstar on October 27, giving its planned direct to device fleet its own mobile satellite spectrum.

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Tesla Semi catches fire in California: what we know

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Credit: KTVU

A Tesla Semi caught fire in Hayward, California, which caused both directions of traffic to shut down for hours before being completely reopened early on Wednesday, the California Highway Patrol said.

The fire occurred just after 5:30 local time in Hayward on Tuesday, as the Semi caught fire in the southbound lanes of I-880 before CHP officials made the decision to shut down both lanes of traffic due to potential risks from hazardous chemical smoke.

There were no injuries reported.

The cause of the fire is currently unknown, as neither Tesla nor the CHP have not determined a cause.

However, some images taken before the Semi was completely destroyed by the fire seem to indicate this might have been an older unit, as it appears to be one of the designs that Tesla shipped as part of its pilot program, before revising it and starting mass production just a month ago.

At the time of publication, CHP had not returned our request for a comment for additional details, including the Semi involved and any potential collaboration on an investigation between the CHP and Tesla. We will update this story when we hear back from them.

The southbound lanes were reopened at 3:30 a.m. on Wednesday, with the northbound lanes opening last night a few hours after the fire began. The CHP did state that the lithium batteries were “incredibly difficult to extinguish,” according to NBC Bay Area.

The truck’s driver said that the Semi caught fire, but he did not have an explanation.

An estimated 5,000 to 7,000 semi-truck and large commercial vehicle fires occur on U.S. roadways every year.

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