Cerro Armazones, located in Chile’s Atacama Desert, has seen significant progress in the construction of the Extremely Large Telescope (ELT). The European Southern Observatory (ESO) has completed the dome’s steel skeleton, marking a milestone in the development of the world’s largest visible- and infrared-light telescope. Expected to have its “first light” by 2028, the ELT’s recent progress was showcased through a stunning nighttime photo capturing the Milky Way’s heart overhead.
Measuring 262 feet high and 289 feet wide, the ELT structure is now being outfitted with dark blue panels as protective insulated cladding. These panels, consisting of various layers including thermal insulation and an aluminum exterior sheet, are crucial for shielding the telescope. They will cover the entire dome, ensuring the telescope’s protection from the harsh environment of the Atacama Desert.
During night operations, the dome will open its large observing slit to scan the sky, while air conditioning will maintain a stable temperature inside the dome during the day. This control of environmental conditions is essential for minimizing image distortion caused by turbulence, allowing the ELT to capture clear and detailed astronomical data.
Another key feature shown in the recent progress photo is the azimuth structure, a central concrete foundation designed to protect the telescope from vibrations. This foundation will support the telescope and its array of scientific instruments for its forthcoming exploration of the cosmos. As ESO notes, the telescope is poised to embark on a journey of nights dedicated to unraveling the mysteries of the universe.