The industrial complex proposal threatens some of the world’s clearest skies for astronomy

The European Southern Observatory is at serious risk of losing clear skies above the Paranal Observatory in Chile’s Atacama Desert because of a proposed industrial complex floated by a subsidiary of a US power company, officials said.

The Paranal Observatory is home to ESO’s Very Large Telescope (VLT), which consists of four telescopes each with a 27-foot (8.2 m) mirror and four auxiliary telescopes with 6-foot (1.8 m) mirrors. Working together, telescopes produce some of the clearest views of the universe. Observatory officials are deeply concerned that the proposed industrial project will go ahead, reducing what Paranal can see and permanently changing night vision in some of the best skies for astronomical research.

Right next door

The project, called ENA, is a proposed green hydrogen project on an industrial scale. The total area of ​​the project will cover more than 7,413 acres of the Atacama and will include a port, ammonia and hydrogen production plants, and thousands of electric generators.

All of this will have to be built from the ground up, as the proposed project site is 3 to 7 miles (5 to 11 kilometers) from the Paranal telescopes. AES Andes submitted an environmental impact assessment of the project to Chilean authorities late last month.

“As with any project, our partnership with local communities and stakeholders is a top priority, ensuring we support local economic development, while maintaining the highest environmental and safety standards,” said Javier Dib, Chile market business leader at AES. Company statement Application announcement.

Well, it’s exactly the environmental impacts that have European Southern Observatory officials worried. The Atacama Desert contains some… The darkest and clearest sky Anywhere on Earth. There is little moisture in the air, which reduces the amount of light absorbed by water in the atmosphere, and it is at high altitude, which reduces the amount of fluctuation that ground-based astronomers typically have to contend with when imaging sources far through the atmosphere.

Paranal’s unique location and influence

From its site in Atacama, Chile, the Very Large Telescope has captured astronomical events both ancient and modern, both in our galaxy and beyond. In 2021 the telescope Jigsaw Of the 42 largest asteroids in the solar system. The space rock trend continued in 2023 when two bands were formed Telescope images revealed One of the effects of NASA’s DART mission, which tested the feasibility of changing an object’s natural orbit in space. In the same year the telescope Spotted gas clouds They may have formed in the wake of the first stars, and just two months ago, a different team used a telescope to take pictures First detailed picture To a star outside our galaxy.

Because of the Atacama’s natural aptitude for astronomy, it is home to several existing and planned telescopes, including Paranal, the Rubin Observatory (which hosts the world’s largest digital camera), and the observatory under construction. Giant Magellan Telescope At Las Campanas Observatory. The LSST camera at the Rubin Observatory is scheduled to shed light for the first time later this year, something to look forward to in Packed with astronomical events.

“Chile, especially Paranal, is a truly special place for astronomy – its dark skies are a natural heritage that transcends its borders and benefits all of humanity,” said Itziar de Gregorio, representative of the European Southern Observatory in Chile, at the observatory. He releases. “It is crucial to consider alternative sites for this massive project so as not to jeopardize one of the world’s most important astronomical treasures.”

In 2022, a team of researchers Found Light pollution over Paranal was much lower than at 27 other major observatories. This research found that two-thirds of the large observatories the team studied actually had 10% more light pollution than assumed normal levels, suggesting that light pollution is already seriously affecting astronomical observations.

“The results emerging from this work send what may be the final call for serious, unambiguous, and uncompromising collective action to reduce light pollution now, whether from artificial light or from sunlight reflected by artificial objects in orbit,” the team wrote. “Failure to take action means a gradual decline in our ability to explore our world.”

Astronomy is under threat

“The proximity of the AES Andes mega-industrial project to Paranal poses a major risk to the purest night skies on the planet,” Director General of the European Southern Observatory, Xavier Barcons, said in an observatory statement. “Dust emissions during construction, increased atmospheric turbulence, and especially light pollution will irreparably affect astronomical observing capabilities, which have so far attracted billions of euros in investments by the governments of ESO member states.”

Infrastructure on Earth is not the only concern of astronomers. Earth’s orbit is crowded with satellites, making it difficult to photograph the night sky. Huge constellations including SpaceX’s Starlink Create strips on Astronomical images As the individual spacecraft crosses the night sky. Such satellites even crowd space telescopes, as seen on some of the Hubble Space Telescopes the pictures. there Cleaning tricks Astronomical images of these lines, however, present a problem.

Light pollution is getting worseaccording to recent research. In 2023, a group of researchers will review more than 50,000 observations made around the world between 2011 and 2022 as part of NOIRLab. Earth at night project. The researchers found that the night sky became 9.6% brighter each year, causing some of the faintest stars in the sky to completely disappear for some stargazers.

The impact of light pollution on the Atacama and astronomy

Eventually, it will replace the Very Large Telescope Very large telescope (I know, creative names), which will be 128 feet (39 meters) wide and is set to become the world’s largest visible-light and infrared telescope. The Extremely Large Telescope will collect 100 million times the light collected by the human eye and reveal details about distant exoplanets, black holes, the evolution of galaxies and the early days of the universe. The telescope will be located near the VLT, at Cerro Armazones, and is now expected to have its first light in 2028 – although ESO Website “The End of This Decade” offers a more cautious take.

“Astronomical observatories can be viewed as the proverbial canary in the coal mine,” the team that assessed the relative darkness of the observatories’ skies wrote in their 2022 paper. “If we can’t even keep canaries alive, we can forget that we can solve light pollution as a global environmental issue.” Moreover, the group pointed out other matters Negative consequences Light pollution will continue, including disruption of circadian rhythms and other negative health consequences for Earth’s biodiversity.

In its statement, ESO called for the relocation of the AES Andes project, noting that relocating the industrial park “remains the only effective way to prevent irreparable damage to the unique Paranal skies.” Meanwhile, the company is awaiting word from Chilean authorities on whether the project’s environmental impact is minimal enough to go ahead as proposed.

The cornerstone of the company’s messaging is to decarbonize its energy matrix and increase the amount of energy derived from renewable sources. There would be a painful irony in the Chilean authorities allowing the green energy project to proceed at the expense of clear skies for astronomers.