By: Sebastián Pérez Márquez
Astronomer and USACH Academic
Director of the Centre for Interdisciplinary Studies in Astrophysics and Space Sciences (CIRAS)
Deputy Director of the Millennium Nucleus on Young Exoplanets and their Moons (YEMS)
Chilean science has reached international standards thanks to the unique quality of our skies. Protecting this resource is a shared duty.
The Antofagasta Region is an invaluable heritage for global science. Its exceptionally dark skies have been fundamental for international observatories such as the Very Large Telescope (VLT) at Paranal to lead discoveries that expand the boundaries of human knowledge. The ongoing construction of the Extremely Large Telescope (ELT) at Cerro Armazones, just a few kilometres from Paranal, promises to radically transform our understanding of the universe. However, this valuable natural resource now faces a serious threat that puts the future of astronomical research in the region at risk.
As highlighted in a recent communiqué from the European Southern Observatory (ESO), on 24 December, AES Andes — a subsidiary of AES Corporation — submitted the Inna industrial megaproject for environmental review. This complex, spanning more than 3,000 hectares, contemplates the construction of a port, green hydrogen and ammonia plants, and a wind farm. Its location, only 5 to 11 kilometres from Paranal Observatory, poses a significant risk due to the possible generation of light pollution, dust emissions and atmospheric turbulence — factors that could seriously affect the quality of astronomical observations.
The recent update to the light pollution standard, which came into force in 2024, seeks to protect astronomical areas. Although it regulates more strictly, it only provides guidance on the amount of blue light permitted. The standard allows a restriction of 1% of blue light in Special Protection Areas — such as astronomical observation areas — which is insufficient for places like Paranal and Armazones, where sky quality is exceptionally high, below 1% of blue light contamination.
Since its inauguration in 1999, Paranal Observatory has been key to transcendent astronomical advances, such as the first image of an exoplanet, the study of planet formation sites such as protoplanetary discs, the study of distant galaxies, stellar censuses that allow us to understand our galaxy, the study of stellar orbits around the supermassive black hole at the centre of the Milky Way, and countless revolutionary research projects. Projects of this magnitude depend on dark and stable skies — conditions that this megaproject puts at risk.
It is essential that Chilean institutions, including our universities and research centres, become actively involved in the environmental assessment process. As an academic community, we must express our concern and demand measures that guarantee the protection of our skies. We cannot let this opportunity pass to protect our natural heritage.
Chilean science has reached international standards thanks to the unique quality of our skies. Protecting this resource is a shared duty. This is not about opposing sustainable energy development, but about finding a balance that allows scientific progress and the transition to clean energy. Now more than ever, we must raise our voices and act in defence of our skies.
The Atacama desert has given us a legacy of connection with the cosmos through centuries of sky observation by both indigenous peoples and the Chilean people, and cultures from all over the world. Relocating the Inna project is the only way to preserve one of the last truly pristine dark skies on Earth. Sustainable development must also be responsible development.
Original source: El Mostrador – 14 January 2025