The European Southern Observatory’s (ESO) Extremely Large Telescope (ELT) is making significant progress in its construction, surpassing the 50% completion milestone. Located in Chile’s Atacama Desert, the ELT will be the largest telescope in the world for visible and infrared light, with a 39-metre main mirror. The telescope dome is being assembled at a rapid pace, with the steel structure taking shape. The mirrors and other components are being built in Europe, with over 70% of the hexagonal segments for the main mirror already manufactured. The ELT’s adaptive optics system, including the impressive M4 mirror, is also progressing well. Additionally, the control system and other necessary equipment for the telescope are being developed or produced. The ELT will be equipped with four scientific instruments, all in their final design phase. The support infrastructure at Cerro Armazones is almost complete, with a technical building and a photovoltaic plant already in operation. Despite delays caused by the COVID-19 pandemic, the remaining 50% of the project is expected to be completed in five years. ESO Director General Xavier Barcons expresses pride in reaching this milestone and highlights the ELT’s potential to revolutionize our understanding of the Universe when it begins scientific observations in 2028.
