![On December 24th, AES Andes, a subsidiary of the US power company AES Corporation, submitted a project for a massive industrial complex for environmental impact assessment. This complex threatens the pristine skies above ESO’s Paranal Observatory in Chile’s Atacama Desert, the darkest and clearest of any astronomical observatory in the world [1]. The industrial megaproject is planned to be located just 5 to 11 kilometres from telescopes at Paranal, which would cause irreparable damage to astronomical observations, in particular due to light pollution emitted throughout the project’s operational life. Relocating the complex would save one of Earth's last truly pristine dark skies.](https://scienceblog.com/wp-content/uploads/2025/01/potw2124a.jpg)
The world’s most pristine astronomical observing site faces an existential threat from a proposed industrial megaproject that would bring city-sized development to Chile’s Atacama Desert, potentially ending decades of groundbreaking space research including work that led to a Nobel Prize.
The development, proposed by AES Andes, would place an industrial complex spanning over 3,000 hectares – comparable in size to the Chilean city of Valparaiso – just 5 to 11 kilometers from the telescopes at Paranal Observatory. The project would include a port, ammonia and hydrogen production plants, and thousands of electricity generation units.
A Unique Scientific Heritage at Risk
“The proximity of the AES Andes industrial megaproject to Paranal poses a critical risk to the most pristine night skies on the planet,” warns Xavier Barcons, ESO Director General. “Dust emissions during construction, increased atmospheric turbulence, and especially light pollution will irreparably impact the capabilities for astronomical observation, which have thus far attracted multi-billion-Euro investments by the governments of the ESO Member States.”
Recent research published in Monthly Notices of the Royal Astronomical Society compared light pollution at 28 major astronomical observatories worldwide, confirming Paranal as the darkest site among them. The observatory’s pristine conditions have enabled major scientific breakthroughs, including capturing the first image of an exoplanet and research on the Milky Way’s central black hole that earned the 2020 Nobel Prize in Physics.
The proposed development comes at a particularly critical time, as the nearby Cerro Armazones site hosts the construction of what will be the world’s largest telescope – the Extremely Large Telescope (ELT).
A Call for Alternative Locations
“Chile, and in particular Paranal, is a truly special place for astronomy — its dark skies are a natural heritage that transcends its borders and benefits all humanity,” explains Itziar de Gregorio, ESO’s Representative in Chile. “It is crucial to consider alternative locations for this megaproject that do not endanger one of the world’s most important astronomical treasures.”
The industrial complex’s environmental impact assessment was submitted by AES Andes, a subsidiary of US power company AES Corporation, on December 24th. Scientists argue that relocating the project is the only effective way to prevent irreversible damage to what has become one of Earth’s most important windows to the cosmos.
The Atacama Desert’s unique combination of atmospheric stability and lack of light pollution has made it an unparalleled natural laboratory for astronomical research. These conditions are essential for projects investigating fundamental questions about the Universe’s origins, evolution, and the search for habitable planets beyond our solar system.
More information about the observatory’s research and current developments can be found at the European Southern Observatory’s website.