Artist's Impression of the European Extremely Large Telescope (E-ELT). One of the
purposes for this telescope is to serach for exoplanets, says Simone Zaggia, of the Inaf Observatory
of Padua: "More importantly we want to find out if their atmospheres contain levels of oxygen or
carbon dioxide or methane or other substances that suggest there is life there. To do that, we need
a giant telescope like the E-ELT."
Source: The Guradian
An article, by Robin McVie, in The Guardian looks at what it will take to build the largest and most powerful telescope in the world atop Cerro Armazone, a 3,000-metre mountain in Chile; part of the construction of this telescope requires engineers to blast away 25-metres of this mountain's top. Blasting is scheduled to begin on June 16; and the telescope will take more than a decade to build, with a completion date sometime in 2025.
The European Extremely Large Telescope (E-ELT) will have a 39-metre mirror. McVie writes about this project, led by Gird Hudepohl, its engineer, who was in charge of a similar astronomical project atop another mountain in Chile.
Given the peak's remote, inhospitable location that might sound an improbable claim–except for the fact that Hudepohl has done this sort of thing before. He is one of the European Southern Observatory's most experienced engineers and was involved in the decapitation of another nearby mountain, Cerro Paranal, on which his team then erected one of the planet's most sophisticated observatories.
The Paranal complex has been in operation for more than a decade and includes four giant instruments with eight-metre-wide mirrors – known as the Very Large Telescopes or VLTs – as well as control rooms and a labyrinth of underground tunnels linking its instruments. More than 100 astronomers, engineers and support staff work and live there. A few dozen metres below the telescopes, they have a sports complex with a squash court, an indoor football pitch, and a luxurious 110-room residence that has a central swimming pool and a restaurant serving meals and drinks around the clock. Built overlooking one of the world's driest deserts, the place is an amazing oasis. (See box.)
Now the European Southern Observatory, of which Britain is a key member state, wants Hudepohl and his team to repeat this remarkable trick and take the top off Cerro Armazones, which is 20km distant. Though this time they will construct an instrument so huge it will dwarf all the telescopes on Paranal put together, and any other telescope on the planet.
When completed, the European Extremely Large Telescope (E-ELT) and its 39-metre mirror will allow astronomers to peer further into space and look further back into the history of the universe than any other astronomical device in existence. Its construction will push telescope-making to its limit, however. Its primary mirror will be made of almost 800 segments–each 1.4 metres in diameter but only a few centimetres thick–which will have to be aligned with microscopic precision.A project of this complexity and longevity has all the potential for technical setbacks and delays in time. Even so, the $1.5-billion project is progressing. As to why this particular location was selected and why astronomers consider it ideal, there is indeed an excellent scientific explanation:
The answer is straightforward, says Cambridge University astronomer Professor Gerry Gilmore. It is all about water. "The atmosphere here is as dry as you can get and that is critically important. Water molecules obscure the view from telescopes on the ground. It is like trying to peer through mist – for mist is essentially a suspension of water molecules in the air, after all, and they obscure your vision. For a telescope based at sea level that is a major drawback.The amount of money might seem large, but we ought to put this number in perspective; when compared to how much nations worldwide have spent on useless wars and military campaigns in the last decade alone (at least a thousand times more, or trillions of dollars), the money is insignificant and has a genuine benefit to science and, moreover, to increasing our knowledge of the universe.
You can read more at [The Guardian]