Is Amazon's ambitious plan to blanket the Earth with internet satellites inadvertently blinding astronomers? A recent study suggests that the satellites forming Amazon's new constellation in low Earth orbit (LEO) are indeed bright enough to cast a shadow over crucial astronomical research.
A significant study, recently published on the online repository Arxiv, has delved into the luminosity of nearly 2,000 of Amazon's Leo satellites. The findings are raising concerns because the spacecraft appear to be exceeding the brightness threshold recommended by the International Astronomical Union (IAU). This guideline is designed to ensure that the growing number of satellites in our skies can coexist harmoniously with the vital work of astronomers.
"Bright satellites pose a particular challenge for the large-scale astronomical surveys being conducted at ground-based observatories like the Vera C. Rubin Observatory," explained lead author Anthony Mallama, an astronomer at the IAU Center for Protection of the Dark And Quiet Sky. "However, their interference isn't limited to Earth-bound telescopes; they can also disrupt orbiting observatories such as the Hubble Space Telescope."
Mallama and his team are no strangers to this issue, having previously investigated the brightness of other satellite networks. Their research has included SpaceX's Starlink, which, with approximately 9,500 satellites, is currently the largest constellation in orbit. They've also examined the colossal BlueBird satellite arrays from AST SpaceMobile. These particular satellites are noteworthy for their massive antennas, spanning 690 square feet (64 square meters), making them the brightest artificial objects visible in the night sky. And for those keeping track, the next generation of BlueBirds are even more immense, boasting antennas that cover nearly 2,400 square feet (223 square meters)!
Mallama pointed out that while Amazon's Leo satellites (formerly known as Project Kuiper) are considerably dimmer than the BlueBirds, they are also slightly fainter than most Starlink satellites. This is partly due to Starlink's lower orbital altitude of around 300 miles (480 km). However, he also noted that Starlink benefits from spending a significant portion of its orbit within Earth's shadow, which naturally reduces its visibility.
But here's where it gets potentially more concerning: Future Amazon Leo satellites are slated to orbit at even lower altitudes, around 366 miles (590 km). This adjustment is expected to further amplify their brightness.
John Barentine, an astronomer at the Silverado Hills Observatory in Tucson, Arizona, and a dark sky expert who was not involved in this new study, observed that Amazon Leo satellites are particularly noticeable and bright during twilight hours. Amazon commenced launching its internet constellation in 2025, and while only 180 satellites are currently in orbit, the company has ambitious plans to expand it to over 3,200 spacecraft.
And this is the part most people miss: Despite these concerns, Mallama expressed appreciation for Amazon's proactive approach. He highlighted that satellite operators like Amazon and SpaceX are actively collaborating with astronomers to mitigate the impact of their satellites. One ingenious method involves making the underside of the spacecraft mirror-like, reflecting sunlight back into space rather than scattering it towards Earth. Another technique is to carefully orient the satellites' components so that the sunlit sides are not visible to ground observers.
Barentine further elaborated that since the initial launch of Amazon's test satellites in 2023, the company's engineers have made strides in reducing the amount of light these orbiting satellites reflect back to Earth, thereby diminishing their visibility in the night sky. "Amazon Leo is a prime example of an operator engaging in dialogue with astronomers early in the design phase of their constellation," Barentine commented. "It's encouraging to see this effort yielding positive results."
Astronomers first raised alarms about the potential impact of satellite megaconstellations on astronomical observations shortly after the initial deployment of SpaceX's Starlink satellites in 2019. Back then, observatories were reporting streaked images caused by the trails left by satellites passing through their field of view. Thankfully, SpaceX has also been working diligently to reduce the brightness of its satellites since then.
However, a prior report, published in November 2025 by Mallama and his colleagues in the journal Monthly Notices of the Royal Astronomical Society, revealed that with the exception of OneWeb satellites (which orbit at a higher altitude of 745 miles or 1,200 km), all other currently operational internet-beaming constellations, including China's Qianfan and Guowang projects, are exceeding the IAU's recommended brightness limits.
What do you think? Is the pursuit of global internet access worth the potential cost to our view of the cosmos? Should there be stricter regulations on satellite brightness, or is the ongoing collaboration between tech companies and astronomers sufficient? Share your thoughts in the comments below – we'd love to hear your perspective!
