Extremely Large Telescope

The Extremely Large Telescope is a ground telescope on Cerro Armazones in Chile and consists of hundreds of hexagonal mirror segments that together form an enormous reflective surface. The facility sits high in the Atacama Desert and includes a rotating dome and several instruments designed to observe infrared light.

The European Southern Observatory began construction in 2014 on Cerro Armazones because of the stable atmospheric conditions there. The facility was planned to push the limits of optical and infrared astronomy.

Scientists from multiple nations collaborate at this astronomical facility to study distant galaxies, exoplanets, and the fundamental properties of the universe.

The high elevation provides clear views but visitors should prepare for thin air and extreme temperature swings. Access to the facility is typically restricted and organized tours are usually required.

The optics use adaptive systems that correct distortions caused by Earth's atmosphere in real time and allow images sharper than many space telescopes. This technology adjusts the mirror elements thousands of times per second to match changing air currents.

Elevation above the sea: 3,046 m

Diameter: 3.75 m

Part of: European Southern Observatory

Website: https://elt.eso.org

GPS coordinates: -24.58930,-70.19160

Latest update: December 12, 2025 22:49