Extremely Large Telescope (ELT)

This telescope gathers light 8 million times more than Galileo’s telescope and 100 million times more than the human eye.

Construction on the ELT project in Chile’s Atacama Desert began in 2014, with the foundation stone laid in 2017. Delays due to the pandemic and technical challenges pushed back the initial 2024 operational date. Alongside the construction of its 85-meter dome, European companies are manufacturing the telescope’s mirrors and auxiliary systems. Over 70% of the main 39-meter mirror’s components have been made, with secondary mirrors in polishing stages. The adaptive M4 mirror, designed to adjust its shape 1,000 times per second to correct atmospheric distortions, is fully integrated, and key components of the adaptive optics system are in testing.

Other systems for the complete setup of the ELT, including control systems and assembly equipment, are also in development or production. The first four scientific instruments have reached the final design stage, and some are ready for production. Much of the ELT’s auxiliary infrastructure is already in place at Cerro Armazones or nearby.

The first half of the project faced delays due to extensive design modifications. Now that production has fully resumed post-pandemic, the remaining half of the ELT project is expected to take just five years to complete, although experts warn of potential uncertainties.

Scheduled for initial scientific observations in 2028, the ESO’s ELT will tackle major astronomical questions, potentially revolutionizing our understanding of the Universe and our place in it.