Threat to Chile's Cerro Paranal Observatory Sparks Concern Among Astronomers

The proposed construction of a 3,000-hectare industrial power plant by AES Andes, a subsidiary of the U.S.-based AES Corporation, has raised alarms about potential light pollution and disruption to one of the world’s premier astronomical sites: the Cerro Paranal Observatory in Chile's Atacama Desert. According to astronomer María Teresa Ruiz, who first alerted the public through a letter to El Mercurio, the project could jeopardize the exceptional darkness of the desert skies essential for astronomical observations.

The energy facility, expected to generate power through wind and photovoltaic sources, is planned to begin operations by 2032 just seven miles from the telescopes of the observatory. The European Southern Observatory (ESO) warned that the construction and operational activities would severely impact the local atmosphere, potentially increasing sky brightness threefold, which would diminish its classification from “excellent dark sky” to “rural sky.” As discussions continue among Chile's government ministries to balance energy development with scientific preservation, ESA highlighted the urgency to protect this invaluable natural asset for the astronomical community.