The BlueWalker 3, a massive next-generation communications satellite, has garnered attention for becoming one of the brightest objects in the night sky, raising concerns about light pollution, according to research published in the journal Nature.
It is noteworthy for its capability to effectively transform regular smartphones into satellite phones, however, its brightness raises concerns about the potential for newer, larger satellites to significantly contribute to light pollution, potentially disrupting astronomical observations and impacting both wildlife and cultural traditions.
Researchers, including Jeremy Tregloan-Reed, an astronomer and assistant professor at the Universidad de Atacama in Chile, fear that the proliferation of mega-constellations of internet satellites, like BlueWalker 3, may alter the night sky significantly.
BlueWalker 3 is now the brightest satellite in low Earth orbit, comparable in brightness to the eighth brightest star visible from Earth, Procyon. Only the Moon, Jupiter, Venus, and seven stars outshine it, according to observations from astronomers in various countries.
The larger a satellite is, the brighter it appears due to its increased surface area for reflecting sunlight. BlueWalker 3’s immense size, with a 64-square-meter (693 square feet) array, contributes to its exceptional brightness. It currently stands as the largest commercial communications array in low Earth orbit, although it serves as a prototype for even larger satellites being developed by AST SpaceMobile, backed by AT&T.
The brighter night sky caused by such satellites can pose challenges for astronomical observations, impeding the visibility of stars, nebulas, and celestial details. It can also disrupt wildlife, especially birds that navigate by starlight. Furthermore, the loss of a clear, starry sky has cultural and spiritual significance.
BlueWalker 3 previously made headlines by enabling audio calls between unmodified smartphones in a remote part of Chile, highlighting its potential to improve global internet access and communication.
Tregloan-Reed hopes that this research will encourage the satellite industry to consider designs that minimize light pollution. Future regulations may even require an assessment of a satellite’s impact on the night sky as part of the authorization process before launch, addressing concerns about the growing problem of light pollution.