🔭 The Largest Eye on Earth Is Rising Above the Atacama

At an altitude of 3,046 metres on Cerro Armazones in Chile’s Atacama Desert, engineers are building the most powerful optical telescope ever attempted: ESO’s Extremely Large Telescope, or ELT.

Its primary mirror will span an astonishing 39 metres — far too large to manufacture as a single piece. Instead, it will function as one perfectly synchronised surface made from 798 hexagonal segments, each about 1.45 metres across. The ELT will collect roughly 100 million times more light than the human eye and more than all existing 8–10-metre-class telescopes combined, observing the Universe in visible and infrared light.

But size is only part of the story.

Earth’s turbulent atmosphere makes stars twinkle — beautiful to us, disastrous for precision astronomy. The ELT’s 2.4-metre adaptive mirror, M4, will be controlled by more than 5,000 actuators, reshaping its surface as often as 1,000 times per second to cancel atmospheric distortion and vibrations almost in real time.

The result could transform the search for life beyond Earth. The ELT will directly image some exoplanets, including potentially rocky worlds in nearby habitable zones, and examine their atmospheres for molecules such as water, methane, carbon dioxide and even oxygen.

First test observations are currently planned for March 2029, followed by the first scientific observations in December 2030.

What will it see first: an Earth-like world, the earliest galaxies — or something astronomers have not yet imagined?

#Astronomy #Space #ELT #Exoplanets #Science #Atacama