ESO's ELT Is Likely As Large As Optical Telescopes Will Get
Bruce Dorminey
Senior Contributor
I cover aerospace, astronomy and host The Cosmic Controversy Podcast.
As the largest optical telescope in the world, the ELT will allow scientists to dive further into our universe than ever before. The ELT’s 39-metre ‘eye on the sky’ will capture some of the clearest images ever taken, with a precision reaching 16 times that of the Hubble Space Telescope. Located 3046 m above sea level, on top of Cerro Armazones in Chile, the ELT’s construction has already begun. Once finished, the ELT will unravel countless mysteries of the Southern hemisphere night sky, observing distant exoplanets and nebulae, gazing into the heart of our own Milky Way and all the way out to the first galaxies in our Universe. This 3D rendering of the telescope shows how it will look as it operates during the night, with its laser guide star units.
Eighteen of the 798 optical mirrors that will make up the largest optical telescope ever built are now on a ship plowing through the North Atlantic enroute from France to Chile’s Atacama Desert. Once this 39-meter behemoth of a telescope is finally completed in about four years time, ground-based astronomy will never be the same.
But as fabulous as it will be, the European Southern Observatory’s Extremely Large Telescope is likely to be an astronomical dinosaur. That’s because a single aperture optical telescope that’s much larger than ESO’s ELT is likely to be technically unfeasible, Luis Chavarria Garrido, ESO’s representative in Chile, told me during a sit-down interview here in Santiago.
For a single aperture telescope more than double the size of the current ELT, a conventional observatory dome would probably not be workable, says Chavarria Garrido. With its 80-meter-tall dome, the current ELT is already pushing current infrastructure technology. So, it will probably be impossible to build the kind of dome needed for a 100-meter telescope, he says.
And if such a monster telescope were left without a dome and simply exposed to the open air, Chavarria Garrido says cleaning and maintaining its mirrors would be problematic.
More:
https://www.forbes.com/sites/brucedorminey/2023/12/23/esos-elt-is-likely-as-large-as-optical-telescopes-will-get/?sh=6f063b472c22
