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SpaceX shares how it's making Starlink satellite less bright. SpaceX shares how it's making Starlink satellite less bright.

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SpaceX shares how it’s making Starlink satellites less bright.

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SpaceX shared how it’s making its Starlink satellites less bright. The space exploration company published a document titled, Brightness Mitigation Best Practices for Satellite Operators that outlines how it’s working with the astronomy community to reduce light pollution.

SpaceX has been criticized for the brightness of its Starlink satellites by astronomers. Elon Musk and the team at SpaceX not only listened to the criticism but are actively responding to it by collaborating with the astronomy community to solve the issue.

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SpaceX Is Making Starlink satellites Invisible to the naked eye.

SpaceX noted that through the collaboration, it has identified and mitigated the key causes of satellite brightness. The company is working on making the satellites invisible to the naked eye when they are at their standard operational altitude.

If satellites are illuminated by the sun at night, they can be visible to observers from the earth. However, the visibility of any satellite depends on the materials used for its surfaces.

Since satellites don’t emit their own light, the brightness results from natural sunlight scattering off of the satellites’ surfaces and reflecting down to earth. The light can scatter in two different ways: specular or diffuse.

SpaceX is focusing on specular scatter

Credit: SpaceX

SpaceX is investing in specular surfaces. Specular light is reflected at a single angle just like a mirror. Diffuse light reflects from many angles. The image above shows the difference between how specular light scatters and diffuse light scatters.

SpaceX noted that not all materials are highly reflective and some can be absorptive or make the light that is reflected much less bright.

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SpaceX’s satellites are visible from the ground in two ways.

  1. Sunlight scatters off the main body.
  2. Sunlight scatters from the solar arrays.

To solve this, SpaceX adopted mitigations for both problems for its current, first-generation satellites.

Sun Visors and RF-Transparent mirror films

starlink
Credit: SpaceX

Sun Visors 

For the first-gen satellites, SpaceX developed sun visors that block sunlight from hitting the bottom side of the chassis (body of the satellite.) They were made from materials that engineers developed to be invisible to radio frequencies.

However, the sun visors blocked the laser links that SpaceX uses to expand coverage to remote regions of the world. Additionally, the visors generated significant drag on the satellites. So, SpaceX determined that the sun visors weren’t a long-term solution.

RF- transparent mirror films.

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SpaceX developed RF-transparent mirror films as an alternative to the sun visors. The film scatters most of the sunlight away from the Earth. SpaceX said that it has been improving its mirror films to scatter less light back to the earth.

It plans to deploy a new and improved version of the film on its next-generation satellites.

Inter-cell backing material

Another change that SpaceX made to its first-gen satellites involved the inter-cell backing material. The material was initially white but SpaceX changed it to a dark red that reduces the arrays’ brightness.

The downside is that the darkening of the material increases the temperature of the solar array which reduces performance. However, SpaceX will adopt many designs such as this one to reduce the brightness of the satellites.

Dielectric Mirror Film for Starlink satellites.

SpaceX noted that its second-gen satellite will add more capacity to the Starlink network; connecting more people in more places.

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The second-gen satellites will use the following three advanced brightness techniques and I will dive into one of them: Dielectric Mirror film.

SpaceX will cover the bottom of the satellites with a second-gen dielectric mirror film. This version reduces the observed brightness ten times better than the first-gen film by using a Bi-Directional Reflectance Distribution Function (BRDF) metric.

You can see how the BRDF for decreases visibility in the chart below.

SpaceX shares how it's making Starlink satellite less bright.

Credit: SpaceX

 

Through extensive research and iteration, SpaceX maximized the film’s specular scatter. The core of the film is a Bragg mirror that includes many thin layers of plastic that have a variety of refractive indices which create interference patterns internally to reflect the light.

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It also allows radio waves to pass through with no issues. Protective layers of titanium dioxide and silicon dioxide were added to protect the film in thin, pure layers that don’t affect the film itself. Below is a comparison between the first-gen and second-gen mirrors.

Credit: SpaceX

 

SpaceX plans to offer the dielectric mirror film as a product

SpaceX plans to offer the dielectric mirror film as a product on the Starlink website. The reason is that SpaceX can not reduce the effect of satellites on space exploration by itself.

The film will be offered at cost and all operators will be able to use it to reduce the effect of their own constellations.

SpaceX will continue to work with the astronomy community

SpaceX emphasized that not only is the astronomy community’s work important but that it would continue to work with them to reduce the effects of all satellite operations.

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“SpaceX is committed to connecting as many people as possible through Starlink, improving the lives of millions of people here on Earth.”

“As a space exploration company, SpaceX is a strong supporter of astronomy and the scientific community.”

You can read the full document here.

I’d love to hear from you! If you have any comments, or concerns, see a typo, you can email me at johnna@teslarati.com. You can also reach me on Twitter @JohnnaCrider1

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Johnna Crider is a Baton Rouge writer covering Tesla, Elon Musk, EVs, and clean energy & supports Tesla's mission. Johnna also interviewed Elon Musk and you can listen here

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SpaceX confirms third massive compute deal at Colossus data center

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Credit: xAI Memphis

SpaceX confirmed today that it has officially signed its third massive compute deal, providing compute at its Colossus data center in Southaven, Mississippi.

Reflection AI will gain immediate access to NVIDIA GB300 chips at SpaceX’s Colossus 2 data center. In return, Reflection will pay SpaceX $150 million per month starting on July 1, with total payments reaching approximately $6.3 billion if the contract runs through its duration, which is until 2029. Either party can terminate the agreement with 90 days’ notice after the initial three-month period.

CNBC first reported the deal.

This latest partnership highlights SpaceX’s strategy of commercializing its massive Colossus supercomputing infrastructure, originally developed to power Elon Musk’s Grok AI models. The company has rapidly expanded its customer base in the AI sector following its February 2026 merger with xAI, a transaction that valued the combined entity at $1.25 trillion.

SpaceX has previously signed significant compute deals with other major players.

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It granted Anthropic exclusive access to the full capacity of its Colossus 1 data center, which exceeds 300 megawatts and includes over 220,000 NVIDIA GPUs. Details from SpaceX’s IPO filings indicate Anthropic will pay $1.25 billion per month through May 2029, potentially generating around $45 billion over the term of the deal.

Additionally, Google agreed to pay SpaceX $920 million per month for compute capacity from October 2026 through June 2029. This 32-month period will provide Google access to roughly 110,000 NVIDIA GPUs, along with supporting processors and memory. Capacity ramps up through September at a reduced fee, with termination options after the first year.

SpaceXA also established arrangements for computing power with Cursor, an AI coding startup. SpaceX acquired them in a $60 billion all-stock deal.

SpaceX makes first acquisition post-IPO

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These arrangements position SpaceX’s collective position as an AI infrastructure powerhouse with high-margin revenue potential. The Google deal alone could generate nearly $29.5 billion over its term, while the Reflection contract adds another $6.3 billion.

Combined with the Anthropic arrangement, SpaceX stands to realize tens of billions in revenue from compute leasing in the coming years, which diversifies beyond SpaceX’s traditional rocket launches and Starlink operation.

The deals underscore growing demand for advanced AI training and inference capacity amid chip shortages and surging model development needs. Reflection, valued at $25 billion and focused on “American open intelligence” with government and national security ties, cited recent restrictions on closed models as validation for open-source approaches.

For SpaceX, the partnerships transform capital-intensive data centers into flexible revenue sources while supporting its broader AI ambitions after the company has gone public.

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Elon Musk responds to SpaceX’s ESG rating and says its rockets won’t go electric

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(Credit: SpaceX)

It is safe to say SpaceX won’t be going for electric rockets anytime soon.

In a characteristically blunt reply on X, SpaceX frontman Elon Musk stated, “Unfortunately, electric rockets are impossible,” following reports that MSCI had assigned SpaceX its lowest possible ESG rating of CCC.

The assessment, issued just this past week, coinciding closely with SpaceX’s public market debut, placed the company on par with nations like Russia in sustainability scoring and cited significant risks in environmental, social, and governance areas.

MSCI flagged SpaceX’s exposure to rocket emissions and other operational impacts, alongside governance concerns such as concentrated control by Musk and limited shareholder protections. Musk’s terse comment directly addressed the environmental pillar, underscoring a core physical constraint that ESG frameworks often overlook when evaluating high-thrust industries.

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Electric propulsion systems do exist and are widely used in space. Ion thrusters and Hall-effect thrusters accelerate ionized propellant, typically xenon or krypton, using electric fields, achieving very high specific impulse, often exceeding 3,000 seconds compared to roughly 300–450 seconds for chemical rockets.

This efficiency makes them ideal for satellite station-keeping, orbit raising, and deep-space missions where low thrust over long durations is sufficient. SpaceX’s own Starlink satellites employ electric propulsion for these purposes.

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However, launching from Earth’s surface demands something entirely different: enormous thrust delivered rapidly to overcome gravity and atmospheric drag. A typical orbital-class booster must generate thrust far exceeding its weight, often in the millions of Newtons within seconds.

Chemical rockets achieve this through exothermic combustion of dense propellants, producing high-mass-flow, high-velocity exhaust. Electric systems, by contrast, expel very small amounts of mass at extremely high speeds. Generating equivalent thrust would require impractical onboard power levels, massive energy storage or generation systems, and prohibitive added mass, rendering the approach infeasible with current or near-term technology.

Musk has previously expressed a similar sentiment, noting a desire for electric orbital rockets while acknowledging the inescapable requirements of Newton’s third law and energy delivery. The distinction is clear: electric propulsion excels once a vehicle is already in space; it cannot replace the high-thrust chemical phase required to reach orbit from the ground.

The episode illustrates broader critiques of ESG ratings. Proponents argue they incentivize better risk management and long-term sustainability. Detractors, including Musk—who has previously called ESG a “scam”—contend that such metrics can penalize essential activities when no practical alternative exists, potentially discouraging innovation in sectors like space access.

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Elon Musk dubs the S&P 500 ESG as “outrageous scam” after Tesla gets booted from index

SpaceX has sought to mitigate launch-related impacts through reusability: Falcon 9 boosters have flown more than 30 times in some cases, dramatically lowering the manufacturing and emissions burden per kilogram delivered to orbit. Starship’s design further emphasizes rapid reusability and methane propellant, which can theoretically be produced via sustainable pathways.

Ultimately, Musk’s remark serves as a reminder that certain engineering realities persist regardless of scoring systems. As humanity expands its presence in space for communications, science, and exploration, balancing genuine environmental progress with technological necessity remains a central challenge.

ESG frameworks may evolve, but the fundamental limits of electric launch propulsion are unlikely to change soon.

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Investor's Corner

SpaceX is launching a secret spacecraft that could change how things are made in space

SpaceX’s secret disk-shaped Starfall capsule is targeting a market no reentry vehicle has cracked.

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SpaceX is targeting Tuesday, June 23 for the first flight of Starfall, a reentry capsule the company has developed almost entirely in private. The Falcon 9 launch window opens at 6:43 a.m. ET from Space Launch Complex 40 at Cape Canaveral Space Force Station, with a backup window available the same time on June 24. SpaceX has made no public announcement about the vehicle, only providing launch details. Everything known about it has come through FAA and FCC regulatory filings.

What makes Starfall different starts with its shape. Rather than the traditional cone used by Dragon and every other cargo return capsule in operation, Starfall is a flat disk that measures roughly  10.2 feet (3.1 meters) wide and just 2.5 feet (0.75 meters) tall, and weighing 4,630 pounds (2,100 kg) and capable of returning up to 2,200 pounds (1,000 kilograms) of payload from orbit. The disk geometry maximizes structural efficiency and payload volume relative to mass, and the heat shield mechanically jettisons just before splashdown, allowing recovery teams to retrieve both the capsule and the shield separately from the Pacific Ocean.

The difference with Starfall from existing competitors, such as Varda Space Industries, which has largely built the orbital manufacturing market and returns heavy payloads per flight is that Starfall’s specification is roughly 30 times more per mission, and is designed to be mass-produced and launched on either Falcon 9 or Starship. That combination of volume and launch access is something no standalone startup can replicate, and it puts SpaceX in direct competition with the companies that currently pay it to reach orbit.

SpaceX to launch military missile tracking satellites through new Space Force contract

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The intended market is orbital manufacturing: pharmaceuticals, protein crystals, semiconductors, and advanced optical fiber that physically cannot be produced in the presence of gravity. FAA documents describe Starfall’s long-term purpose as building a “self-sustaining commercial in-space manufacturing market” and as a potential successor to the industrial capabilities of the International Space Station, which is set to retire in the late 2020s. Military rapid global cargo delivery is a parallel application under active discussion with the Pentagon.

The reason some industries seek manufacturing in space comes down to gravity. On Earth, gravity causes materials to settle, separate, and deform during production. In microgravity, those constraints disappear.

SpaceX’s already controls launch access, which means it currently functions as the landlord for every competitor in the orbital manufacturing return space. Starfall converts that landlord position into vertical ownership, and it would no longer just carry other companies’ capsules to orbit, but rather operate the capsule, own the return logistics, and capture the service revenue directly. Viewed alongside Starlink, Colossus, and the xAI merger, Starfall fits a consistent pattern: SpaceX identifying infrastructure layers that others depend on and moving to own them outright. Orbital manufacturing return is the next layer on that list.

If Tuesday’s reentry, parachute sequence, and recovery demonstration goes as planned, the second FAA-approved test flight follows. A successful pair of demos would position SpaceX to begin offering Starfall as a commercial service, likely first to pharmaceutical and materials science customers before scaling toward the military and broader manufacturing segments.

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