The global scientific community is welcoming what many call a significant victory for astronomy after Chile’s environmental regulator confirmed the cancellation of a proposed $10 billion industrial development that scientists warned could have irreversibly damaged some of the clearest and darkest skies on Earth.
The project, known as the INNA megaproject, was a sprawling industrial complex planned by AES Andes — a subsidiary of U.S.-based AES Corporation — on a 3,000-hectare site in northern Chile’s Atacama Desert. While officially pitched as a green hydrogen, green ammonia and renewable energy facility featuring solar and wind components, the proposal quickly provoked alarm among astronomers worldwide because of its proximity to major observatories, including the European Southern Observatory’s (ESO) Paranal Observatory and the under-construction Extremely Large Telescope (ELT).
Scientists had consistently argued that even with modern environmental planning, the operation of such a large industrial facility so close to world-class telescopes would introduce light pollution, ground vibrations, dust contamination and increased atmospheric turbulence, all of which could jeopardise precision astronomical observations. According to analyses from ESO, the proposed INNA development could have increased sky brightness around the Very Large Telescope (VLT) by as much as 35%, a level deemed incompatible with maintaining world-class observation conditions.
Pressure from the scientific community culminated in an open letter, spearheaded late last year by Nobel laureate Reinhard Genzel and signed by dozens of leading astronomers from around the world, calling on authorities to reconsider the project’s location and prioritise protections for the internationally recognised dark skies of the Atacama.
On Monday, AES Andes announced it would “desist from the execution of the INNA project” and instead focus on other renewable energy and storage initiatives, a decision welcomed by both scientific organisations and environmental advocates. Chile’s environmental assessment service later confirmed the withdrawal of the proposal, formally ending the most contentious phase of the project’s review.
European Southern Observatory Director General Xavier Barcons expressed relief at the cancellation, emphasising that the planned site “would have posed a major threat to the darkest and clearest skies on Earth and to the performance of the most advanced astronomical facilities anywhere in the world.” Barcons and other astronomy leaders also underscored that while the cancellation was a win for scientists, it highlights the ongoing need for stronger legal protections around key observatory regions.
The Atacama Desert region, perched more than 2,600 metres above sea level and far from urban light pollution, has long been prized for its unique atmospheric conditions, making it home to some of the most powerful and productive telescopes ever built. Among these, the VLT and the ELT — the latter expected to be the largest optical telescope in the world when it begins scientific operations — have offered insights into distant galaxies, exoplanets and fundamental questions about the universe.
The cancellation also resonates beyond Chile’s borders, prompting renewed calls from scientists and advocacy groups to establish more formal and enforceable measures to protect astronomical sites as part of global heritage and environmental stewardship efforts.
While Chile continues to host a concentration of cutting-edge astronomical infrastructure, experts say the episode has renewed discussions about how best to balance the nation’s role in combating climate change using renewable technologies with the world’s scientific interest in preserving its extraordinary skies.
