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SpaceX "DARKSAT" results: can Starlink and astronomy happily coexist?

New results should improve confidence that SpaceX's Starlink constellation - with a little time and effort - should eventually be able to happily coexist with astronomy. (SpaceX)

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Astronomers have begun to gather and analyze detailed observations of a SpaceX Starlink satellite prototype officially labeled DARKSAT and the initial results hint that the satellite constellation should be able to happily coexist with ground-based astronomy in the future.

Since SpaceX began launching batches of 60 Starlink satellites in May 2019, the company has raised the ire of parts of the astronomy community and simultaneously awed and inspired many less technical observers with clusters of shooting star-like satellites that are easily visible after launches. While the mid-sized spacecraft do become much dimmer as they raise their orbits from ~300 km (185 mi) to 550 km (340 mi), they are far from invisible even at that operational altitude. It’s safe to say that the current impact on ground-based astronomy is still just shy of negligible even with 360 satellites in orbit, but that impact is assuredly greater than zero and the relatively bright spacecraft have already interrupted telescope observations at many sites around the world.

Given that the 360 satellites already in orbit are just a tiny fraction of the ~4400, ~12,000, or even ~40,000 that SpaceX could one day launch, it would be irresponsible to argue that the constellation’s impact – and the impact of others like it – will continue to be minor as the number of satellites grows. Thankfully, while it doesn’t appear that prospective low Earth orbit (LEO) constellation architects anticipated the potential astronomy impact, SpaceX’s Starlink team has rapidly responded and already launched a satellite featuring tweaks designed to dim its appearance from the ground. For several reasons, the initial results from “DARKSAT” are extremely promising – now visible below in some of the first photos offering a useful comparison.

Launched on January 7th, 2020, a set of 20 spacecraft including DARKSAT – representing a single “plane” of the broader Starlink constellation – all arrived at their operational ~550 km (340 mi) orbits by February 23rd. As previously discussed on Teslarati, initial results first published on March 18th revealed that the Starlink DARKSAT prototype – essentially an early alpha test for darkening techniques – was already 55% darker than unmodified spacecraft. While making satellites less reflective makes thermal management a much greater challenge, DARKSAT has managed to raise its orbit and begin operations without issue, although it’s unknown whether the satellite’s antennas and avionics are also functioning nominally.

Falcon 9 B1049 lifted off for the fourth time with a batch of 60 Starlink satellites on January 7th. (Richard Angle)

For darker spacecraft, perhaps the most important test will be long-term reliability, as constantly absorbing more heat than a reflective satellite is likely to put their structure, avionics, and radiators through significantly more thermal stress. As such, SpaceX may launch a limited number of additional darkened prototypes over the coming months but is much less likely to darken all satellites on any given launch until DARKSATs have successfully operated in orbit for months or even years.

On the ground, SpaceX may try to perform sped-up stress testing, but proving that darker satellites are a viable solution will almost invariably take time. Earlier this month, CEO Elon Musk revealed that SpaceX may attempt to design deployable solar shades for Starlink satellites if darkening their bodies is not enough to fully mitigate major impacts to astronomy. Knowing SpaceX, the first in-orbit solar shade test(s) could happen during any of several upcoming Starlink launches.

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While all satellites struggle with thermal management and typically rely on mirror-like foil insulation and shiny surfaces to stay cool, Starlink’s uniquely flat and rectangular design makes it exceptionally reflective. (Teslarati – SpaceX)

Adding reliable, deployable solar shades without appreciably raising Starlink’s production costs could be a major challenge, given the fundamental complexity of large, deployable mechanisms in space, but SpaceX – if anyone – is likely up to the challenge. More importantly, the fact that SpaceX’s very first attempt at reducing Starlink albedo (reflectivity) has produced a satellite 55% darker than its peers suggests that much more can probably be done along those lines, given additional time for extra experiments and deeper optimization.

As a result, it may be the case that SpaceX ends up launching 750-1000+ reflective Starlink satellites before an affordable, mass-producible DARKSAT variant is ready to take over. In that event, Starlink could plausibly have a small to moderate negative impact on ground-based astronomy for several years. However, comments made by SpaceX executives over the years suggest that no single Starlink satellite is likely to operate for more than five or so years before being replaced, meaning that the entire constellation would be continuously refreshed (as long as it’s generating revenue). Even if a thousand bright(er) Starlink satellites make life a bit harder for some astronomers, the fact remains that the consequences of any single Starlink satellite variant – assuming SpaceX remains serious about fully mitigating the constellation’s impact – are inherently temporary.

An animation of SpaceX’s Starlink satellite constellation. (SpaceX – gif by Teslarati)

If SpaceX continues to make progress darkening satellites and developing cheap solar shades, it seems all but guaranteed that even a constellation of tens of thousands of Starlink satellites will be able happily coexist with the astronomy community, all the while delivering cheap, fast internet to millions of people – especially those lacking access – around the world.

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 China roars back with highest vehicle registrations this Q2 so far

Tesla China’s 80% week-over-week growth was the most notable among Chinese EV brands.

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Credit: Tesla China

Tesla China saw a notable rise in new vehicle registrations in the week of June 9 to 15, 2025. During the week, Tesla China’s registrations saw an impressive 80% week-over-week increase, resulting in the electric vehicle maker posting its highest insurance registration figures this Q2 so far. 

Tesla China Roars Back

During the week ending June 15, 2025, Tesla China saw 15,500 insurance registrations. This represents an 80% increase from the previous week’s 8,640 units. This is also the highest number of registrations that Tesla has posted in China for the past ten weeks, as noted in a CNEV Post report.

Tesla watchers have observed that the electric vehicle maker’s 80% week-over-week growth was the most notable among Chinese EV brands. Following Tesla was Xpeng, which saw a 52% week-over-week growth to 6,400 registrations, and Nio, which saw a 9.3% week-over-week increase to 4,700 registrations. 

Tesla China does not report its weekly vehicle registration figures, though the company’s overall performance in the Chinese auto market can be inferred through new vehicle registration data. Fortunately, these registrations are closely tracked and reported by industry watchers, as well as automakers like Li Auto.

Tesla Model Y Impact

Industry watchers estimate that Tesla China was able to deliver 11,200 new Model Y units to customers in the week ending June 15. This represents a week-over-week improvement of about 85% from the previous week. This bodes well for the revamped all-electric crossover, as it suggests that demand for the vehicle remains strong.

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The new Model Y is Tesla’s highest volume seller. Thus, it would not be a surprise if the company’s numbers this Q2 2025 end up relying on the sales figures of the revamped all-electric crossover. Fortunately, Tesla has two more weeks before the quarter ends, which should be enough to increase its quarterly sales numbers to a notable degree.

Tesla’s domestic sales in China totaled 38,588 units in May, down 30% year-over-year but up 34% percent from April, as per data from the China Passenger Car Association (CPCA). In the same month, Giga Shanghai also exported 23,074 vehicles in May.

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SpaceX Ax-4 Mission prepares for ISS with new launch date

SpaceX, Axiom Space, and NASA set new launch date for the Ax-4 mission after addressing ISS & rocket concerns.

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SpaceX-Ax-4-mission-iss-launch-date
(Credit: SpaceX)

SpaceX is preparing for a new launch date for the Ax-4 mission to the International Space Station (ISS).

SpaceX, Axiom Space, and NASA addressed recent technical challenges and announced a new launch date of no earlier than Thursday, June 19, for the Ax-4 mission. The delay from June 12 allowed teams to assess repairs to small leaks in the ISS’s Zvezda service module.

NASA and Roscosmos have been monitoring leaks in the Zvezda module’s aft (back) segment for years. However, stable pressure could also result from air flowing across the hatch seal from the central station. As NASA and its partners adapt launch schedules to ensure station safety, adjustments are routine.

“Following the most recent repair, pressure in the transfer tunnel has been stable,” a source noted, suggesting the leaks may be sealed.

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“By changing pressure in the transfer tunnel and monitoring over time, teams are evaluating the condition of the transfer tunnel and the hatch seal between the space station and the back of Zvezda,” the source added.

SpaceX has also resolved a liquid oxygen leak found during post-static fire inspections of the Falcon 9 rocket, completing a wet dress rehearsal to confirm readiness. The Ax-4 mission is Axiom Space’s fourth private astronaut trip to the ISS. It will launch from NASA’s Kennedy Space Center in Florida on a Falcon 9 rocket with a new Crew Dragon capsule.

“This is the first flight for this Dragon capsule, and it’s carrying an international crew—a perfect debut. We’ve upgraded storage, propulsion components, and the seat lash design for improved reliability and reuse,” said William Gerstenmaier, SpaceX’s vice president of build and flight reliability.

The Ax-4 mission crew is led by Peggy Whitson, Axiom Space’s director of human spaceflight and former NASA astronaut. The Ax-4 crew includes ISRO astronaut Shubhanshu Shukla as pilot, alongside mission specialists Sławosz Uznański-Wiśniewski from Poland and Tibor Kapu from Hungary. The international team underscores Axiom’s commitment to global collaboration.

The Ax-4 mission will advance scientific research during its ISS stay, supporting Axiom’s goal of building a commercial space station. As teams finalize preparations, the mission’s updated launch date and technical resolutions position it to strengthen private space exploration’s role in advancing space-based innovation.

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Sweden blocks Tesla FSD-style testing in Stockholm

It looks like FSD testing in Sweden would have to wait some time.

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Credit: Tesla AI/X

Tesla is putting a lot of effort into getting its Full Self Driving (FSD) system approved in territories outside North America. But while China seems to have embraced FSD fully, other countries like Sweden do not seem to be receiving Tesla’s automated driving system very well.

This became quite evident in a document from Stockholm City, which has started making the rounds online.

FSD Testing Rejected

The document, which was initially shared by X user @KRoelandschap, indicated that the Swedish Traffic Department in Stockholm had rejected Tesla’s request to start FSD testing in the city’s streets. Tesla has been demonstrating FSD in several areas across Europe, so it is not surprising that the company is also attempting to test its automated driving system in Sweden.

Unfortunately for Tesla, Sweden might prove to be a tough nut to crack. As per the City of Stockholm: 

“The Traffic Office is currently working on updating its approach to automation. At the same time, the city and the office are under heavy pressure from other ongoing innovation tests. Our ambition is to actively participate in and learn from the continued development in the field of automation. 

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“Based on this, and in combination with the fact that the current test is the first of its kind, which entails certain risks for both infrastructure and third parties, and that it is planned to be carried out throughout the city, the City of Stockholm considers it is currently not possible to approve the implementation of the test.”

Tesla’s Other Swedish Troubles

Sweden’s FSD testing rejection is not the only roadblock facing Tesla in the country. Since October 2023, Swedish unions have been engaged in an active effort to disrupt Tesla’s operations. The unions’ efforts have been varied, with some resulting in Tesla having difficulty launching more Superchargers in Sweden. Despite this, Tesla has remained stubborn and has refused to bow to the unions’ demands.

Fortunately for Tesla, it seems like its numbers are still strong. Despite the company’s decline in several European countries, the new Model Y is starting to see strong sales figures in Sweden. In early May alone, the new Model Y became the country’s most popular electric vehicle—a notable accomplishment considering the unions’ active efforts to disrupt Tesla.

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