Researchers have made a fascinating discovery about one of the brightest objects visible from Earth: it’s not a celestial body, but a communications satellite known as BlueWalker 3. Built by AST SpaceMobile, this satellite resembles a Tetris block and has a peak brightness that rivals some of the brightest stars in the night sky.
However, this brightness poses a significant challenge for ground-based astronomy. The reflection of BlueWalker 3 leaves streaks that can compromise data in telescope images, impacting the accuracy of astronomical observations. Space-based astronomy is also affected, with streaks caused by satellites in lower Earth orbit increasingly disrupting observations from the Hubble telescope.
Recognizing the impact of such bright satellites, the aerospace industry, policymakers, astronomers, and others are working towards finding solutions to mitigate their effects. However, the trend of launching larger and brighter satellites continues, as AST SpaceMobile plans to launch a constellation of satellites called BlueBirds in the future.
One concern arising from BlueWalker 3’s radio frequency usage is its potential interference with radio astronomy. If these frequencies interfere with radio waves from celestial sources, it will make it harder for scientists to study the universe and gain a deeper understanding of its mysteries.
A team of amateur and professional astronomers from different countries collaborated to study the impact of BlueWalker 3 on the night sky. They revealed that the brightness of satellites like BlueWalker 3 is influenced by their distance from Earth, with those in low Earth orbit appearing much brighter than geostationary satellites.
Even if the reflective brightness of all satellites was reduced, the cumulative effect of having hundreds of thousands of satellites in low Earth orbit would still increase the sky’s background glow. Previous studies have also raised concerns about the increasing brightness in the night sky due to artificial objects, further emphasizing the need to address this issue.
Scientists are calling for a cap on the number of low-altitude satellites to reduce light pollution and preserve the ability to study the night sky. It is crucial to preserve the dark skies for future generations, allowing them to marvel at the wonders of the universe through unobstructed observation.