Connect with us

News

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)

Published

on

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.

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.

Advertisement
-
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.

Advertisement
Comments

Elon Musk

Elon Musk says Tesla’s Roadster demo could be a bang, quite literally

Musk says tonight’s Roadster demo will be a banger, maybe literally. The clues add up.

Published

on

By

tesla roadster elon musk flying

Elon Musk spent Wednesday and Thursday stacking teases on top of Tesla’s Roadster event, and the wording is getting harder to read as routine hype. Tesla streams the unveil tonight at 7:55 p.m. Central on X. Musk has called it “a candidate for greatest product demo of all time,” then added that “this demo will be a BANGER, probably metaphorically, though some chance literally.”

The “some chance literally” part is the line to watch. The Roadster has been tied to a SpaceX option package since 2018, and as we reported when the date was announced, the system is reportedly codenamed A71 and uses cold gas thrusters fed by a composite overwrapped pressure vessel, the same tank design SpaceX uses on Falcon 9. Musk has said a thruster equipped car could reach 60 mph in about 1.1 seconds. Cold gas thrusters firing at full output are loud, and reports ahead of the event say the car will be unmanned with spectators kept several hundred yards back. A literal bang could simply mean a demonstration that sounds like one, though it is also an admission that something could go wrong on stage.

Then there is “Timing is everything,” which Musk posted a day earlier. Stocktwits noted that 7:55 p.m. is 19:55 on a 24 hour clock, which echoes 1955, the year Marty McFly travels to in Back to the Future. Musk has made that connection before. In 2019 he replied to an animation of a flying DeLorean by saying the new Roadster “will actually do something like this.” Nothing from Tesla confirms the movie reference, but the stream time was chosen by someone, and Tesla has not been shy about this kind of wink.

Also, Tesla said it moved the event because it “can only be held outdoors,” and Musk then wrote that the demo was postponed “due to high winds,” as Teslarati covered at the time. A car running a standing start in front of a crowd shrugs off wind. A car that leaves the ground does not. The venue near SpaceX’s McGregor test site and the FAA airspace closures reported around the original date point the same way, though we also noted the delay could be a plain safety precaution. Musk has also described the new Roadster as “beyond movies, beyond imagination, beyond human, yet still made by humans on Earth.”

The only official figures remain the 2017 ones: 620 miles of range, a top speed above 250 mph, a 1.9 second 0 to 60 time, and prices of $200,000 for the base car and $250,000 for the Founders Series. Production is expected at Giga Texas in 2027 or 2028. Tesla has said the event will cover pricing, specifications and production targets, and its livestream preview has the full rundown. Tesla reports third quarter earnings on October 21, so whatever lands tonight will be fresh going into that call. We will have live coverage as soon as the stream starts.

Continue Reading

Elon Musk

Elon Musk breaks his silence on the Starlink impact to Ukraine drones

Musk says the US military and president set Starshield limits, not SpaceX, amid Ukraine complaints.

Published

on

By

Elon Musk says the speed limit cutting out Ukraine’s military Starlink terminals is not SpaceX’s decision. In a post on X Wednesday, Musk wrote that “Starshield systems are owned and controlled by the US government. Any limits on speed or usage are decided by the US military and ultimately POTUS.” He added that Starlink is a commercial service limited to civilian or defensive activities and “cannot be used for offensive military action, as doing so would be inappropriate for a commercial company.”

He was replying to Mykhailo Fedorov, Ukraine’s former defense minister, who had thanked Musk for restoring connectivity at speeds up to 160 km/h and said removing the Starshield limit entirely is “now critical for Ukraine’s defense.”

The complaint started Tuesday night, when Ukrainian officials said military terminals began losing service above roughly 100 mph. Presidential adviser Serhiy Beskrestnov said the defense forces got no warning and several missions were disrupted, as Teslarati reported earlier Wednesday. The 7th Rapid Reaction Corps told Reuters connections dropped for 10 to 20 seconds at speeds well below the limit, which made drones harder to control. Poland’s foreign minister, Radoslaw Sikorski, asked Musk on X whether he is “playing politics with your products again.”

That is why the Starlink and Starshield distinction matters. SpaceX introduced Starshield in 2022 as the government version of Starlink, with an initial focus on Earth observation, communications and hosted payloads. It won a Space Force contract in 2023 with a $70 million ceiling. In December 2024, the Pentagon moved Ukraine’s terminals onto Starshield, covering about 3,000 units across two contracts. Ukraine’s military connections therefore run through a service that Musk now says sits under Washington’s control.

SpaceX pitches subscription model for Trump’s Golden Dome

While Musk’s post describes who holds authority, it does not infer that anyone ordered the limit, and neither SpaceX nor the US government has confirmed who set it. Ukrainian officials have pointed to the timing, which follows President Trump’s push for an energy ceasefire and Musk’s Saturday post that “Zelensky has gone too far.” The BBC noted Trump denied threatening to restrict intelligence sharing with Kyiv, and no evidence has been presented that Washington requested the cap.

The episode also revives a promise from 2025. After Poland accused him of threatening Ukraine’s access, Musk said Starlink “will never turn off its terminals” and would not be used as a bargaining chip. Poland has since supplied more than 29,000 terminals to Ukraine. Teslarati also covered Kyiv’s search for Starlink alternatives in 2025, and the latest dispute gives that search new urgency.

Continue Reading

Investor's Corner

Tesla opens the Q&A for its biggest earnings call yet

Tesla opens its Q3 earnings Q&A, and Cybercab, Robotaxi, Optimus and regulators loom over October 21.

Published

on

By

Tesla has opened its shareholder question portal for the Q3 2026 earnings call, with the Say Q&A page already listing questions. Investors have until 4:00 p.m. EDT on October 20 to submit and vote on what management should answer.

The call is set for Wednesday, October 21. Tesla will post results after the market closes, with a live webcast at 4:30 p.m. CT, or 5:30 p.m. ET, through its investor relations site.

Say ranks questions by the number of shares behind the votes, which gives institutional holders extra weight over the retail crowd.

Ahead of Q2, retail investors asked why Robotaxi growth had stalled, when Cybercab would start customer rides, and where the Optimus Gen 3 ramp stood, while an institutional holder asked how Tesla and SpaceX would split Terafab duties. Cybercab has since answered one of those. Tesla said last week it has 300 plus Cybercabs serving Austin, up eightfold in 30 days, with Dallas named as the next city. The questions now are likely to move from when to how fast.

There is also a regulatory question hanging over the call. NHTSA has demanded sworn answers on how the pedal free Cybercab was certified against federal safety standards, with responses due October 30, nine days after the call. Whether an analyst raises it live is unknown, but it is the kind of exposure that tends to find its way into a Q&A.

The numbers will not be the main draw. Tesla already reported 486,532 deliveries and 13.7 GWh of storage for the quarter. Consensus sits around 43 to 45 cents per share on roughly $27.8 billion in revenue, according to Zacks, after a Q2 report that missed on EPS. Goldman Sachs, which holds a Neutral rating and a $360 target, argues the outlook for Robotaxi, FSD and Optimus will matter more to the stock than the quarter itself.

The call also lands six days after the rescheduled Roadster event, which Tesla will stream on X on Thursday, October 15, at 7:55 p.m. CT. If the Roadster shows up with a production date or a SpaceX thruster package, expect it to climb the voting list before the deadline.

Continue Reading