Read our COVID-19 research and news.

Astronomers ink deal to build record telescope

The European Extremely Large Telescope will be built in northern Chile.

ESO/L. Calçada/ACe Consortium

Astronomers ink deal to build record telescope

Astronomers today signed an unprecedented contract to build the world’s largest ground-based optical and infrared telescope. In a ceremony at the headquarters of the European Southern Observatory (ESO) in Garching, Germany, ESO Director General Tim de Zeeuw inked the record deal—worth €400 million—with three Italian engineering firms. They will build the structure that will hold the huge 39-meter mirror of the European Extremely Large Telescope (E-ELT), as well as the domed building that will enclose it. (Watch a video about the new telescope design.)

The agreement “gives ESO the opportunity to be the first in the era of giant telescopes,” De Zeeuw told an online press conference. The light-collecting area of the E-ELT is greater than that of all ground-based optical research telescopes currently in operation, and it will produce images 15 times as sharp as the Hubble Space Telescope. Roberto Tamai, E-ELT program manager, said the telescope will provide “a transformational step in our understanding of the universe.”

Ground-based astronomy is in the throes of a giant leap forward from today’s roughly 10-meter-wide scopes to much bigger instruments. In addition to E-ELT, two other behemoths are under construction: the 25-meter Giant Magellan Telescope at Las Campanas Observatory in Chile and the Thirty Meter Telescope (TMT) at Mauna Kea in Hawaii (although the TMT is currently stalled because of local opposition).

Although ESO has struggled to fully fund the €1.1 billion E-ELT project from its 15 member countries, it has maintained momentum by delaying some components until a later phase II. Tamai says that 90% of the funds for phase I (covering the full telescope and most other components) are in ESO’s bank accounts, but phase II will have to wait. “Construction will be a magnet for new members,” he says. ESO is hoping that Brazil and Russia may come on board.

Gianpietro Marchiori, president of the EIE group which, along with the firms Astaldi and Cimola, forms the ACe consortium that will assemble the scope, described the enormous structure to be built on Cerro Armazones in Chile. The dome will be 80 meters high, weigh 5000 tons, and have a footprint the size of a soccer pitch. The mass of the moving part of the telescope—holding the mirror—will be 3000 tons. The structure will contain 70 kilometers of cabling and 30 million bolts, and will take a total of 4.8 million person-hours to design and build. To walk from the entrance to the roof of the dome will take 30 minutes, Marchiori says.