Bird's eye view of the ELT's altitude structure

The evening sun bathes the construction site of ESO's Extremely Large Telescope (ELT) in red light. This drone image, taken early January 2025, reveals the metal altitude structure inside the dome, which is 50 metres high and will carry the ELT's five mirrors. It rotates so that it can be pointed at different parts of the sky. The 'spider' on top will hold the telescope's secondary mirror, the perforated structure below carries the main mirror, and the central tower supports the ELT's remaining three mirrors.