Space
SpaceX shares how it’s making Starlink satellites less bright.
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.
New document from @SpaceX https://t.co/aI17WdaqrF
explaining what they have been doing to make their satellites less bright.
I applaud SpaceX for their work on this (and for making the document public), while remaining concerned to see how bright the Gen2 Starlinks end up being— Jonathan McDowell (@planet4589) July 29, 2022
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.
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
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.
SpaceX’s satellites are visible from the ground in two ways.
- Sunlight scatters off the main body.
- 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
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.
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.
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.
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.
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.
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.
“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
Investor's Corner
SpaceX IPO is coming, CEO Elon Musk confirms
However, it appears Musk is ready for SpaceX to go public, as Ars Technica Senior Space Editor Eric Berger wrote an op-ed that indicated he thought SpaceX would go public soon. Musk replied, basically confirming it.
Elon Musk confirmed through a post on X that a SpaceX initial public offering (IPO) is on the way after hinting at it several times earlier this year.
It also comes one day after Bloomberg reported that SpaceX was aiming for a valuation of $1.5 trillion, adding that it wanted to raise $30 billion.
Musk has been transparent for most of the year that he wanted to try to figure out a way to get Tesla shareholders to invest in SpaceX, giving them access to the stock.
He has also recognized the issues of having a public stock, like litigation exposure, quarterly reporting pressures, and other inconveniences.
However, it appears Musk is ready for SpaceX to go public, as Ars Technica Senior Space Editor Eric Berger wrote an op-ed that indicated he thought SpaceX would go public soon.
Musk replied, basically confirming it:
As usual, Eric is accurate
— Elon Musk (@elonmusk) December 10, 2025
Berger believes the IPO would help support the need for $30 billion or more in capital needed to fund AI integration projects, such as space-based data centers and lunar satellite factories. Musk confirmed recently that SpaceX “will be doing” data centers in orbit.
AI appears to be a “key part” of SpaceX getting to Musk, Berger also wrote. When writing about whether or not Optimus is a viable project and product for the company, he says that none of that matters. Musk thinks it is, and that’s all that matters.
It seems like Musk has certainly mulled something this big for a very long time, and the idea of taking SpaceX public is not just likely; it is necessary for the company to get to Mars.
The details of when SpaceX will finally hit that public status are not known. Many of the reports that came out over the past few days indicate it would happen in 2026, so sooner rather than later.
But there are a lot of things on Musk’s plate early next year, especially with Cybercab production, the potential launch of Unsupervised Full Self-Driving, and the Roadster unveiling, all planned for Q1.
News
SpaceX reportedly mulling IPO, eyeing largest of all time: report
“I do want to try to figure out some way for Tesla shareholders to participate in SpaceX. I’ve been giving a lot of thought to how to give people access to SpaceX stock,” Musk said.
SpaceX is reportedly mulling an initial public offering, eyeing what would be the largest valuation at the time of availability of all time, a new report from Bloomberg said on Tuesday.
It is one of many reports involving one of Elon Musk’s companies and a massive market move, as this is not the first time we have seen reports of an IPO by SpaceX. Musk himself has also dispelled other reports in the past of a similar nature, including an xAI funding round.
SpaceX and Musk have yet to comment on the report. In the past, untrue reports were promptly replied to by the CEO; this has not yet gained any response, which is a good sign in terms of credibility.
However, he said just a few days ago that stories of this nature are inaccurate:
“There has been a lot of press claiming SpaceX is raising money at $800B, which is not accurate. SpaceX has been cash flow positive for many years and does periodic stock buybacks twice a year to provide liquidity for employees and investors. Valuation increments are a function of progress with Starship and Starlink and securing global direct-to-cell spectrum that greatly increases our addressable market. And one other thing that is arguably most significant by far.”
There has been a lot of press claiming @SpaceX is raising money at $800B, which is not accurate.
SpaceX has been cash flow positive for many years and does periodic stock buybacks twice a year to provide liquidity for employees and investors.
Valuation increments are a…
— Elon Musk (@elonmusk) December 6, 2025
Musk has discussed a potential IPO for SpaceX in recent months, as the November 6 shareholder meeting, as he commented on the “downsides” of having a public company, like litigation exposure, quarterly reporting pressures, and other inconveniences.
Nevertheless, Musk has also said he wants there to be a way for Tesla shareholders to get in on the action. At the meeting in early November, he said:
“I do want to try to figure out some way for Tesla shareholders to participate in SpaceX. I’ve been giving a lot of thought to how to give people access to SpaceX stock.”
Additionally, he added:
“Maybe at some point., SpaceX should become a public company despite all the downsides of being public.”
Musk has been historically reluctant to take SpaceX public, at times stating it could become a barrier to colonizing Mars. That does not mean it will not happen.
Bloomberg’s report cites multiple unidentified sources who are familiar with the matter. They indicate to the publication that SpaceX wants to go public in mid-to-late 2026, and it wants to raise $30 billion at a valuation of around $1.5 trillion.
This is not the first time SpaceX has discussed an IPO; we reported on it nine years ago. We hope it is true, as the community has spoken for a long time about having access to SpaceX stock. Legendary investor Ron Baron is one of the lucky few to be a SpaceX investor, and said it, along with Tesla, is a “lifetime investment.”
Tesla bull Ron Baron reveals $100M SpaceX investment, sees 3-5x return on TSLA
The primary driver of SpaceX’s value is Starlink, the company’s satellite internet service. Starlink contributes 60-70 percent of SpaceX’s revenue, meaning it is the primary value engine. Launch services, like Falcon 9 contracts, and the development of Starship, also play supporting roles.
SpaceX reached an incredible milestone with its Starlink program with a launch last night, as the 3,000th satellite of the year was launched into low Earth orbit.
On Monday, SpaceX also achieved its 32nd flight with a single Falcon 9 rocket from NASA’s Kennedy Space Center.
The mission was Starlink 6-92, and it utilized the Falcon 9 B1067 for the 32nd time this year, the most-used Falcon booster. The flight delivered SpaceX’s 3000th Starlink satellite of the year, a massive achievement.
There were 29 Starlink satellites launched and deployed into LEO during this particular mission:
Falcon 9 launches 29 @Starlink satellites from Florida pic.twitter.com/utKrXjHzPN
— SpaceX (@SpaceX) December 9, 2025
SpaceX has a current goal of certifying its Falcon boosters for 40 missions apiece, according to Spaceflight Now.
The flight was the 350th orbital launch from the nearby SLC-40, and the 3,000 satellites that have been successfully launched this year continue to contribute to the company’s goal of having 12,000 satellites contributing to global internet coverage.
There are over five million users of Starlink, the latest data shows.
Following the launch and stage separation, the Falcon 9 booster completed its mission with a perfect landing on the ‘Just Read the Instructions’ droneship.
The mission was the 575th overall Falcon 9 launch, highlighting SpaceX’s operational tempo, which continues to be accelerated. The company averages two missions per week, and underscores CEO Elon Musk’s vision of a multi-planetary future, where reliable connectivity is crucial for remote work, education, and emergency response.
As Starlink expands and works toward that elusive and crucial 12,000 satellite goal, missions like 6-92 pave the way for innovations in telecommunications and enable more internet access to people across the globe.
With regulatory approvals in over 100 countries and millions of current subscribers, SpaceX continues to democratize space, proving that reusability is not just feasible, but it’s also revolutionary.
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