Have you ever looked up at the night sky and wondered what those moving dots of light might be? Chances are, you're not seeing shooting stars—you're watching satellites. And here's something that might surprise you: there are now so many of them up there that astronomers are genuinely worried about their ability to do their jobs.
Amazon recently launched its internet-beaming constellation into orbit, joining SpaceX's Starlink and others in a race to blanket Earth with connectivity. But there's a problem. According to a groundbreaking study released this month, these satellites shine too brightly—so much so that they're interfering with the very telescopes trying to unravel the universe's mysteries.
This isn't just about inconvenience. We're talking about potential disruptions to decades of astronomical research, from hunting for near-Earth asteroids to mapping distant galaxies. At FreeAstroScience.com, we believe in keeping science accessible and minds alert—because as Goya reminded us, "the sleep of reason breeds monsters." So let's dive into what's happening above our heads and why it matters to all of us.
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What Makes Amazon's Satellites Too Bright for Astronomy?
Picture this: nearly 2,000 observations, one clear conclusion. That's what astronomer Anthony Mallama and his colleagues analyzed when they examined Amazon's LEO (Low Earth Orbit) satellites, also known as Project Kuiper. Their findings, posted to the preprint server ArXiv on January 12, 2026, weren't encouraging.
The satellites have an average apparent magnitude of 6.28 [web:4]. Now, you might think that sounds faint—and it is, at least to your naked eye under typical conditions. But for professional astronomers? It's a nightmare. The study found that a staggering 92% of these spacecraft exceed the brightness limit recommended by the International Astronomical Union (IAU).
The IAU's Centre for Protection of the Dark and Quiet Sky established two critical thresholds. Satellites shouldn't exceed magnitude 7 to avoid messing with professional telescopes—that's the research limit. They should also stay dimmer than magnitude 6 to prevent ruining our aesthetic appreciation of the night sky. Amazon's satellites are pushing right up against that second threshold.
Here's what makes this particularly troubling: Amazon currently has around 180 satellites in orbit, but the company has approval to deploy 3,236 of them. They're required to have half the constellation (roughly 1,618 satellites) up there by July 2026, and the full fleet by July 2029. We're just seeing the beginning of this problem.
How Do Satellites Interfere with Telescopes?
Think of it like trying to photograph a distant, faint object while someone keeps flashing a mirror in your direction. That's essentially what happens when a satellite crosses a telescope's field of view.
Mallama, who works at the IAU Center for Protection of the Dark and Quiet Sky, explained that bright satellites are "particularly troublesome for large-scale astronomical surveys being conducted at ground-based observatories such as the Vera C. Rubin Observatory". But it doesn't stop there. "However, they can also interfere with orbiting observatories like the Hubble Space Telescope," he added.
In about 25% of observations, Amazon's satellites appeared bright enough to be visible without telescopes. When that happens, the imaging data gets contaminated with streaks and artifacts—especially during twilight periods when both the satellites and astronomical targets are illuminated by the sun.
The Vera Rubin Observatory faces a particular challenge because of its extreme sensitivity and wide field of view. Estimates suggest that 30-40% of images taken early and late at night could be compromised by satellite trails [web:20]. This matters enormously because the observatory's mission includes detecting near-Earth objects—asteroids that might pose a collision risk to our planet. These objects need to be observed during the same twilight windows when satellites are most visible.
Space telescopes aren't immune either. Recent modeling suggests that if the 560,000 satellites currently planned are deployed, one in every three Hubble images would contain at least one satellite trail. For newer missions like SPHEREx and China's Xuntian telescope, more than 96% of exposures would be affected.
Which Satellite Constellations Are the Brightest?
Not all satellites are created equal when it comes to brightness. Let's compare the major players orbiting above us right now.
AST SpaceMobile's BlueBird satellites take the crown—or the curse, depending on your perspective. These massive spacecraft have antennas spanning 690 square feet (64 square meters), making them the brightest artificial objects in the night sky [web:4]. The next-generation BlueBirds are even larger, with antennas nearly 2,400 square feet (223 square meters).
SpaceX's Starlink constellation, with around 9,500 satellites, is currently the largest in orbit [web:4]. Most Starlink satellites are somewhat brighter than Amazon's LEO spacecraft, partly because they operate at a lower altitude of about 300 miles (480 kilometers) compared to Amazon's 391 miles (630 kilometers). Lower altitude means they appear brighter from Earth. However, Starlink benefits from spending more time in Earth's shadow during each orbit, which reduces visibility.
New Starlink variants pose an even bigger concern. A study from mid-2024 found that SpaceX's Direct-To-Cell satellites have an average magnitude of 4.62—making them 4.9 times brighter than other Starlink spacecraft.
Amazon's LEO satellites sit in the middle of this spectrum. They're considerably dimmer than BlueBirds and somewhat less bright than most Starlinks [web:4]. But here's the catch: future Amazon satellites are expected to operate at lower altitudes around 366 miles (590 kilometers), which may increase their brightness further.
A November 2025 report by Mallama and colleagues in the Monthly Notices of the Royal Astronomical Society painted a grim picture: nearly all operational internet-beaming constellations, including China's Qianfan and Guowang systems, exceed IAU-recommended brightness limits. OneWeb satellites at higher altitudes were the sole exception.
Are Ground and Space Telescopes Both Affected?
The short answer? Yes, absolutely. But the way they're affected differs.
Ground-based observatories deal with what John Barentine, an astronomer at Silverado Hills Observatory in Tucson, Arizona, calls the "twilight problem". Amazon's satellites seem particularly bright during those precious hours before dawn and after dusk when astronomers hunt for specific types of objects. During these windows, satellites are still illuminated by the sun while the ground is dark enough for observations.
The Vera Rubin Observatory represents a worst-case scenario. Its Large Synoptic Survey Telescope (LSST) is designed to repeatedly scan the entire visible sky, creating a constantly updated map of the universe. This means it can't simply avoid satellites—they'll inevitably cross its field of view. Small debris just a few centimeters across could create millisecond-duration flares that form detectable streaks in images.
Space telescopes face different but equally serious challenges. You'd think orbiting above Earth's atmosphere would protect them, but satellites at lower altitudes can still photobomb their images. The Hubble Space Telescope, our beloved window to the cosmos since 1990, now faces an increasing number of satellite trails in its exposures.
NASA has tried to downplay the concern, characterizing streaks in current Hubble images as "faint" and noting that "most of these streaks are readily detected and removed using standard data reduction techniques". But that's missing the point. Even if you can remove the streaks afterward, the data from that part of the image is lost forever. As one researcher put it: "That part of the image will be forever lost".
Infrared telescopes like SPHEREx face an additional problem: satellites can reflect infrared light even when mitigation techniques reduce their optical visibility. This means darkening coatings that work for visible light don't necessarily solve the problem across all wavelengths.
What Is Amazon Doing to Reduce Satellite Brightness?
Here's some good news: Amazon hasn't ignored astronomers' concerns. In fact, they've been relatively proactive compared to some competitors.
"Amazon Leo is an instance in which the operator established a dialogue with astronomers early in the design phase of their constellation," said John Barentine. "It is encouraging to see that this effort has yielded some success."
Since launching test satellites (KuiperSat-1 and KuiperSat-2) in October 2023, Amazon engineers have worked on reducing reflected light through several techniques:
- Mirror-like coatings on satellite undersides to reflect light away from Earth rather than scattering it
- Adjusting spacecraft orientation to minimize sunlit surfaces visible from the ground
- Ongoing brightness monitoring and iterative design improvements
The company launched its first batch of 27 operational satellites in April 2025, followed by additional launches throughout the year. By October 2025, they had 153 satellites in orbit. These operational spacecraft incorporate the brightness mitigation features developed after the 2023 prototypes.
The fact that Amazon engaged with astronomers before finalizing their satellite design sets them apart. Many other constellation operators only addressed brightness concerns after widespread criticism from the scientific community.
Still, the results show there's more work to do. With 92% of satellites exceeding the IAU's research limit, current mitigation efforts haven't been sufficient to meet the recommended standards.
What Does This Mean for Astronomy's Future?
We're at a crossroads. The next few years will determine whether humanity can have both global satellite internet and pristine views of the cosmos—or whether we'll have to choose.
The math is sobering. If all currently approved satellite constellations are deployed, we'll have around 560,000 active satellites in orbit. Some proposals under consideration would push that number closer to one million. At that scale, nearly every image taken by ground or space telescopes would contain satellite trails.
One proposed mitigation strategy involves placing large satellite constellations below the altitude of space telescopes, where spacecraft spend more time in Earth's shadow and appear dimmer. But this creates new problems. Lower orbits mean satellites burn up more frequently due to atmospheric drag, and recent research suggests materials released during reentry may harm the ozone layer. Lower orbits also make satellites appear brighter to ground-based observatories, potentially shifting the problem rather than solving it.
We need a coordinated approach. The IAU's guidelines represent a starting point, but they're voluntary. No international treaty currently regulates satellite brightness, though some scientists have called for legally binding agreements to protect Earth's orbit.
There's also the cultural dimension. Dark skies have inspired humanity since we first looked up. They're where we've found gods, navigated oceans, and pondered our place in the universe. A magnitude 6 satellite might not seem bright, but multiply that by thousands and you fundamentally alter something that's been constant throughout human history.
For astronomers, the stakes are even higher. Projects like mapping dark matter, searching for Earth-like exoplanets, and detecting potentially hazardous asteroids depend on our ability to see faint, distant objects. Satellite interference doesn't just annoy researchers—it actively limits what questions we can ask about the universe.
Amazon has shown that engaging with the astronomical community can lead to improvements. Now we need that approach scaled up across the entire industry, backed by regulations with teeth. We have the engineering capability to build darker satellites—the question is whether we have the collective will to demand them.
At FreeAstroScience.com, we craft content to keep your mind engaged with the wonders of science, precisely because informed citizens make better decisions about challenges like this. The night sky belongs to all of us. Whether it stays visible is up to us too.
About This Article
This article was researched and written for you by FreeAstroScience.com, where we're committed to making science simple and accessible. We believe that staying curious and informed keeps our minds sharp and engaged—because understanding the universe around us is too important to leave to chance. Visit us anytime to explore more science stories that matter.
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Note: This article incorporates information from the January 2026 study on Amazon LEO satellite brightness by Anthony Mallama and colleagues, as well as supporting research on satellite constellation impacts on astronomy. All sources are cited and listed above for verification and further reading.
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