Amazon's Project Kuiper, now known as Amazon Leo, faces new criticism. A recent study found that 92% of its operational satellites are too bright for astronomical research. This brightness exceeds recommended limits set by the International Astronomical Union (IAU). The study, published on ArXiv on January 12, 2026, analyzed nearly 2,000 observations of Amazon's internet-beaming satellites. It highlights growing concerns about how large satellite constellations affect scientific observations and the night sky.[news+3]
Satellites Exceed Research Limits
The study's findings are clear. Amazon Leo satellites have a mean apparent brightness of 6.28 magnitude. The IAU's Centre for the Protection of the Dark and Quiet Sky (CPS) sets a "research limit" of approximately magnitude 7.15 for satellites at Amazon's operating altitude of 391 miles (630 kilometers). A lower magnitude number means a brighter object. This means Amazon's satellites are significantly brighter than astronomers recommend.About 25% of the observations showed satellites bright enough for people to see with their bare eyes in dark areas. For comparison, the faintest stars visible to the unaided eye in a perfectly dark sky are around magnitude 6.0.[news+4]
This unwanted light causes big problems for ground-based observatories. Large-scale surveys, like those done by the Vera C. Rubin Observatory, are especially vulnerable. Bright streaks from satellites can saturate sensitive digital cameras. This permanently corrupts valuable data.The problem is not just for ground telescopes. The study also noted that these bright satellites can interfere with orbiting observatories, such as the Hubble Space Telescope.[news+2]
Anthony Mallama, an astronomer at the IAU Center for Protection of the Dark And Quiet Sky, led the study. He emphasized the severe impact on research. "Bright satellites are particularly troublesome for large-scale astronomical surveys being conducted at ground-based observatories such as the Vera C. Rubin Observatory," Mallama told Space.com. "However, they can also interfere with orbiting observatories like the Hubble Space Telescope."[dailygalaxy]
Amazon's Efforts to Reduce Brightness
Amazon has been talking with the astronomy community about these issues. The company has tried to make its satellites less reflective. They use dielectric mirror films on the underside of the spacecraft. These films aim to reflect sunlight away from Earth. Amazon also adjusts the satellite's position to reduce the visible area of sunlit parts from the ground.[news+1]
John Barentine, an astronomer at the Silverado Hills Observatory, confirmed some success. He stated that Amazon engineers reduced reflected light from their 2023 test satellites.Despite these efforts, the new study suggests that current measures are not enough. The brightness levels still exceed the IAU's guidelines.[primetimer+2]
Amazon plans a massive constellation of 3,236 satellites. Currently, about 180 Amazon Leo satellites are in low Earth orbit.The sheer number of planned satellites raises ongoing worries for astronomers. They fear the cumulative effect of so many bright objects in the night sky.[popsci+2]
Future Concerns and Next Steps
Amazon has Federal Communications Commission (FCC) approval to operate its satellites at various altitudes. The current satellites orbit at about 391 miles (630 kilometers). Amazon plans to lower the altitude of future Kuiper satellites to around 366 miles (590 kilometers).While a lower altitude means a satellite is visible for less time during each pass, it can make them appear brighter to observers directly below.This creates a complex challenge for mitigation efforts. The study authors warned that these changes might not fully solve the brightness issue.[news+5]
The increasing number of satellite constellations from various companies is a growing concern for scientists worldwide. In 2019, there were roughly 2,000 satellites in orbit. Today, that number is around 15,000.The IAU and NSF NOIRLab will continue to monitor the Amazon Leo constellation. This ongoing observation will happen as Amazon launches more satellites to meet its FCC deployment deadline in mid-2026.[ca+1]
The study highlights a critical tension. Companies want to expand space-based internet services. Astronomers want to preserve dark skies for scientific research and public enjoyment. Finding a balance will require continued cooperation and potentially new regulations to ensure space remains usable for everyone.[news+2]
