The latest research published in the journal Nature reveals that the BlueWalker 3, a state-of-the-art communications satellite, has become one of the brightest objects visible in the night sky. While BlueWalker 3 is revolutionary for its ability to transform ordinary smartphones into satellite phones, it also hints at a potential downside: the rise of satellite-generated light pollution. The rapid growth of mega-constellations of internet satellites is already hindering astronomers’ ability to observe celestial bodies beyond Earth, and BlueWalker 3, as the brightest satellite in low Earth orbit, is just the beginning of this problem.
Jeremy Tregloan-Reed, an astronomer and assistant professor at the Universidad de Atacama in Chile and one of the authors of the Nature paper, warns that if this issue is not addressed promptly, it could drastically alter the night sky. He emphasizes the urgency of nipping this problem in the bud before it becomes an irreparable issue. Tregloan-Reed acknowledges the potential benefits of advanced satellites like BlueWalker 3 in improving internet access and communication worldwide, especially in underserved areas. Nevertheless, he believes that the industry and consumers should prioritize technologies that minimize light pollution.
The research highlights that BlueWalker 3 is currently as bright as the eighth brightest star visible from Earth, Procyon. Only the Moon, Jupiter, Venus, and seven stars in the night sky appear brighter than this satellite. The observations utilized data collected by professional and amateur astronomers from various countries, including Chile, the United States, Mexico, New Zealand, the Netherlands, and Morocco.
The primary reason behind BlueWalker 3’s remarkable brightness is its size. Typically, larger satellites are brighter due to their increased surface area, enabling them to reflect more light. With a 64-square-meter (693 square feet) array, BlueWalker 3 has the largest commercial communications array in low Earth orbit. However, this title may soon pass to even larger satellites currently under development by AST SpaceMobile, with support from AT&T.
The excessive brightness of satellites like BlueWalker 3 can interfere with telescopic observations. These star-like objects crossing the sky create photobombing effects that make it challenging to identify constellations. Additionally, the increased sky background glow caused by these bright satellites hinders the visibility of nebulas, dust clouds, and other intricate details in the night sky.
Moreover, a brighter night sky has adverse effects on wildlife, especially birds that rely on starlight for navigation. Culturally and spiritually, our ability to stargaze has profound significance. However, due to the growing light pollution, research suggests that a child born in an area where 250 stars are visible at night may only see 100 stars by the time they reach 18 years old.
Nevertheless, the positive impact of satellites like BlueWalker 3 cannot be ignored. Earlier this year, BlueWalker 3 achieved a groundbreaking feat by successfully routing an audio call between two unmodified smartphones without the need for cell towers. Professor Tregloan-Reed, working in rural Chile, understands the potential benefits of such advanced satellite technology in bridging the digital divide and enhancing global communication. However, he hopes that his research will prompt the industry and consumers to prioritize technologies that minimize light pollution.
Companies involved in satellite development may need to modify their designs to reduce the amount of light reflected by their satellites. Additionally, future regulations might require a thorough assessment of a satellite’s impact on the night sky as part of the authorization process before launch. Taking proactive steps now will serve to protect the night sky and preserve its natural beauty for future generations.
