Ética & Regulação
Astronomy at Risk: ESO Calls for 100,000-Satellite Limit
Dr. Adrian Vale
LLM, AI Agents & AI Infrastructure Specialist
5 min read
Original sourceLLM, AI Agents & AI Infrastructure Specialist
The European Southern Observatory (ESO) has proposed a limit of 100,000 satellites in Earth's orbit to combat increasing light pollution from mega-constellations like SpaceX's Starlink. With over 1.7 million satellite launches planned, unchecked growth threatens ground-based research telescopes, such as the Extremely Large Telescope (ELT). The ESO calls for international regulations on satellite brightness and deployment limits.
The European Southern Observatory (ESO) has issued a significant warning about the escalating number of satellites orbiting Earth. In a study published in Astronomy & Astrophysics, the organization proposes limiting the total number of satellites in low-Earth orbit (LEO) to 100,000. This measure aims to curb the adverse effects of light pollution on astronomical research.
Currently, over 1.7 million satellite launches are planned globally in the coming decades. This figure vastly exceeds the proposed cap and could jeopardize the performance of advanced ground-based telescopes, such as the Extremely Large Telescope (ELT), which is being developed to explore the universe’s earliest galaxies and exoplanets. The increase in satellite mega-constellations, led by companies like SpaceX (Starlink) and Amazon (Kuiper), has raised alarms within the scientific community due to its potential to disrupt celestial observations.
With the growing presence of satellite constellations, light pollution has emerged as a critical challenge for astronomy. As satellites reflect sunlight, they create bright streaks across the night sky, interfering with the ability of telescopes to detect faint celestial objects. Even low-reflectivity satellites contribute to these disruptions, albeit to a lesser extent.
One of the most visible examples of this problem is the formation of "satellite trains," where groups of satellites moving in unison create bright, moving streaks across the sky. This phenomenon not only disrupts scientific observations but also diminishes the cultural and aesthetic value of the night sky, which UNESCO considers part of humanity’s shared heritage.
Despite the growing challenges posed by satellite proliferation, there is currently no unified global framework to regulate the total number of satellites, their brightness, or their positioning.
The ESO study outlines several measures to mitigate the problem:
Without such measures, the future of ground-based astronomy could be at serious risk, potentially hampering critical research into topics like dark matter, exoplanets, and the origins of the universe.
If implemented, the proposed cap on satellite numbers would significantly affect companies like SpaceX, Amazon, and OneWeb. These organizations rely on deploying large constellations to provide global internet services and other commercial applications, making them particularly vulnerable to new regulations.
The next steps toward addressing this growing issue will rely on coordinated international efforts. Organizations like the International Telecommunication Union (ITU) and national space agencies must take the lead in crafting and implementing effective regulatory frameworks.
The ESO's proposed cap on satellite numbers is a call to action for governments, industry leaders, and international organizations to prioritize the protection of astronomy and the night sky. As satellite technology continues to expand, balancing innovation with sustainability will be crucial to ensuring that the wonders of the universe remain accessible to both scientists and future generations.
The ESO suggests this limit to address light pollution caused by satellite mega-constellations, which interfere with ground-based astronomical research and hinder the observation of faint celestial objects.
Over 1.7 million satellite launches are planned in upcoming years, far exceeding ESO's proposed cap of 100,000 satellites in Earth's orbit.
Satellite mega-constellations create reflective light pollution, causing streaks that interfere with telescopes observing deep space, making it difficult to study faint celestial objects and phenomena.
💡 Dica Pro: Satellite operators can explore advanced materials like dark coatings and non-reflective surfaces to mitigate light pollution from their orbital assets, reducing their impact on astronomy without compromising functionality.
