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A steel Starship soars around the Moon in this official render. (SpaceX) A steel Starship soars around the Moon in this official render. (SpaceX)

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SpaceX to mature Starship Moon landing and orbital refueling tech with NASA’s help

In order for SpaceX to land Starship on the Moon, the company will need to master the high-volume orbital transfer of propellant between two spacecraft. (SpaceX)

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NASA has announced 19 technology partnerships between the agency’s many spaceflight centers and 13 companies, including SpaceX, Blue Origin, and more. This round of Space Act Agreements (SAAs) shows a heavy focus on technologies and concepts that could benefit exploration of the Moon and deep space more generally, including lunar landers, food production, reusable rockets, and more.

Put simply, all 19 awards are great and will hopefully result in tangible products and benefits, but SpaceX has a track record of achievement on the cutting edge of aerospace that simply has not been touched over the last decade. As such, the company’s two SAAs are some of the most interesting and telling, both ultimately focused on enabling Starship launches to and landings on the Moon and any number of other destinations in the solar system. Perhaps most importantly, it signals a small but growing sect within NASA that is willing and eager to acknowledge Starship’s existence and actively work with SpaceX to both bring it to life and further spaceflight technology in general.

One agreement focuses specifically on “vertically land[ing] large rockets on the Moon”, while the other more generally seeks to “advance technology needed to transfer propellant in orbit”, a feature that Starship’s utility would be crippled without. In this particular round of SAAs, they will be “non-reimbursable” – bureaucratic-speak for a collaboration where both sides pay their own way and no money is exchanged. SpaceX’s wins ultimately show that, although NASA proper all but refuses to acknowledge Starship, the many internal centers it is nothing without are increasingly happy to extend olive branches towards the company and its ambitious next-generation rocket.

“SpaceX of Hawthorne, California, will work with NASA’s Kennedy Space Center in Florida to advance their technology to vertically land large rockets on the Moon. This includes advancing models to assess engine plume interaction with lunar regolith.”

“SpaceX will work with Glenn and Marshall to advance technology needed to transfer propellant in orbit, an important step in the development of the company’s Starship space vehicle.”


NASA, July 30th, 2019

A steel Starship on the Moon. (SpaceX)

Giant rockets on the Moon

SpaceX’s first SAA centers around studying the task of landing Starship – a “large rocket” – on the Moon and attempting to understand just how the Moon’s powdery regolith (i.e. inorganic topsoil) will respond when subjected to the plume of a Raptor engine. Put simply, the task of landing a spacecraft as massive as Starship has never been attempted on the Moon, and the process itself – irrespective of any potential surprises from plume-regolith interaction – poses some obvious challenges.

In the most basic sense, Starship is massive. According to the vehicle’s circa. 2018 dimensions, it will stretch 55m (180 ft) from nose to tail, be 9m (30 ft) in diameter, and weigh (per 2017 specs) ~85 tons (190,000 lb) empty and upwards of ~1350 tons (2.95 million lbs) fully fueled. For reference, that is almost 80% as tall and more than 2.5 times as heavy as an entire Falcon 9 rocket. In the history of lunar exploration, Apollo’s Lunar Module (LM) – including landing and ascent stages – is the heaviest vehicle to have ever landed on the Moon, weighing a maximum of 5500 kg (12,100 lb) at landing (Apollo 17).

Apollo 14’s Lunar Module is pictured here after landing on the Moon in 1971. (NASA)

As such, an expendable Starship landing on the Moon with zero propellant for a possible return to Earth would easily break the record for landed mass by a factor of 10-20, while a Starship landing with enough delta V to simply return to lunar orbit – let alone land back on Earth – could easily up that to 30-50x.

Aside from the mass of Starship, there is also the question of how to gently land the spacecraft in the first place. Lunar gravity is roughly 1/6th of Earth’s, meaning that, say, 200 tons (i.e. Raptor’s thrust) would equate to more than 1200 tons of effective thrust on the Moon, a more than 10:1 thrust-to-weight ratio. For reference, the Apollo Lunar Module descent stage was powered by an engine with ~10,000 lbf (4.5 tons) of thrust that could throttle as low as ~1000 lbf (0.45 tons), meaning that even in lunar gravity conditions, the LM could have a thrust-to-weight ratio less than 1. For the purpose of safely landing on the Moon and ensuring a gentle landing, that is an extremely desirable thing to have.

Known as ullage thrusters, an official render shows Starship using the small thrusters to settle its propellant ahead of Raptor ignition. (SpaceX)

Much like Falcon 9’s upper stage features cold-gas nitrogen thrusters to settle its propellant before MVac ignition, Starship will likely need a similar system, and it’s possible that that system could be used to gently land Starship and tweak its velocity in the final stages of a Moon landing. This study will likely be used in part to figure out what exactly the optimal method of landing Starship is.

How to Refuel Your Starship

Finally, SpaceX’s second NASA SAA focuses on developing the immature technology of in-orbit propellant transfer, an absolute necessity for Starship to simultaneously be fully reusable and capable of landing significant payloads on other planets (or moons). Ever since SpaceX CEO Elon Musk first revealed the company’s Mars-bound launch vehicle in 2016, it has incorporated in-orbit refueling as a foundational feature.

These official c. 2017 renders show the broad-strokes process of on-orbit refueling. (SpaceX)

Due to the additions required for full reusability, Starship will essentially need to be launched into Earth orbit and then quickly refueled anywhere from 1 to 10+ times depending on the ultimate destination and the mass of the cargo being delivered. This is not to say that Starship will be useless without refueling – according to SpaceX VP of Sales Jonathan Hofeller, Starship will be capable of launching more than 100 tons (220,000 lb) to low Earth orbit and 20 tons (44,000 lb) to geostationary transfer orbit (GTO), more than enough to satisfy every commercial demand currently in existence.

However, with one or several refueling missions, Starship should be able to turn 100 tons to LEO into 100 tons to the surface of Mars or dozens of tons to the surface of the Moon. Put simply, with reliable and fast refueling, Starship goes from being a major step forward in reusable spaceflight to the key to the solar system and to radically affordable deep spaceflight.

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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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