Astronomers celebrate cancellation of $10bn Chile project that threatened clearest skies in the world

The scientific community is celebrating the cancellation of a project which would have threatened the clearest skies in the world in Chile’s Atacama Desert.The proposed $10bn, 3,000-hectare green hydrogen and ammonia production facility, known as INNA, included a port, transport links to the coast and three solar power plants, and had been under evaluation by Chile’s environmental regulator for almost a year.Astronomers had warned repeatedly that its proximity to some of the world’s most powerful telescopes would have irreparably damaged observation in the area, which is the best site in the world for ground-based astronomy.“This cancellation means that the INNA project will no longer have a negative impact on the Paranal Observatory,” said Itziar de Gregorio, the European Southern Observatory’s (ESO) representative in Chile, where it operates three telescope complexes.“However, what this megaproject has brought to the table is the urgent need for clear protection measures around the sites where professional astronomy is carried out in Chile. This cancellation does not mean that the work to protect the skies is over.”Chile’s environmental evaluation service confirmed that, following meetings last week with AES Andes – the company which had proposed the facility – the project has now been formally withdrawn.Scientists had warned that the INNA facility would affect readings by raising light pollution, causing tiny vibrations in the earth which would affect instruments, aerialise dust which could settle on the mirrors of its precision telescopes, and increase atmospheric turbulence.They argued that there was no need to place the facility so close to the observatories given the potentially disastrous consequences for astronomy.Aes Andes, a subsidiary of US company AES Corporation which generates energy in Chile, Colombia and Argentina, with coal, gas, hydroelectric, wind and solar plants, did not immediately respond to a request for comment.However, in a press release it said: “After detailed analysis of its portfolio of projects, [AES Andes] has decided to cease the execution of the INNA project,” although it added that it was “absolutely compatible” with other activities in the area.An open letter published in December, led by 2020 Nobel Prize winner Reinhard Genzel, had urged the Chilean government to kill the proposed project, as the facility would have been just 11.6km from Paranal, one of the world’s most important observatories.Its Very Large Telescope (VLT), built 2,600m above sea level, has taken the readings that have won three Nobel prizes. And on nearby Cerro Armazones, the Extremely Large Telescope (ELT) – will be the largest and most powerful telescope ever built – is under construction.It will allow astronomers to scour distant galaxies for Earth-like exoplanets that might support life.