TUCSON, Ariz. (KGUN) — Construction is underway on a next-generation optical telescope, up to 200 times more powerful than the best telescopes in use today.

All seven mirrors of the giant Magellan telescope are made right here at the University of Arizona.

“No other university in the world has a production facility like this,” said Mirror Polishing project scientist Hubert “Buddy” Martin.

The production facility is the Richard F. Caris Mirror Lab at the University of Arizona. It’s a hidden gem of the university, tucked under the east side of Arizona Stadium.

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Although hidden, the laboratory is known worldwide for its cutting-edge development of optical telescope mirrors.

“All these 8.4 meter mirrors are the largest mirrors ever made,” Martin explained.

They are currently manufacturing the seven mirrors of the giant Magellan telescope which will be located in Chile.

But to better understand what they are doing today, we have to go back to the beginning, to the early 1980s.

“Roger Angel and John Hill and some of their colleagues developed a method of lightweight mirrors,” Martin said.

In 1985, Dr. Angel, with financial support from the University of Alberta, the U.S. Air Force and the National Science Foundation, began the mirror laboratory located under Arizona Stadium.

“We grew this company to make mirrors that were better than anything available and now they’ve gone into many telescopes that the University of Alberta is a partner in,” Martin said.

One of their first mirrors can still be found in Vatican Observatory, Pope’s Telescope, on Mount Graham near Safford, Arizona. The 1.8 meter mirror is the first mirror Buddy Martin worked on.

Foundation of the Vatican Observatory

“It was the first one made by spin casting,” Martin said. “We spin the furnace while the glass melts and the centrifugal force naturally gives it the parabolic surface area you need for a telescope.”

From there, the mirror lab used rotational casting to create even larger mirrors.

Richard F. Caris Mirror Lab at the University of Arizona

“The challenge is if you make it bigger, it doesn’t want to hold its shape precisely,” Martin explained. “A telescope mirror must maintain its shape to about a millionth of an inch.”

The Mirror Lab has solved this problem by now projecting 8.4 meter mirrors. This is almost 28 feet in diameter.

They have now cast the seven mirrors of the giant Magellan. The six exterior mirrors have a unique saddle shape.

“That’s because we put seven of them together to function as a single primary mirror 25 meters in diameter,” Martin explained.

University of Arizona and GMTO Corporation

It takes approximately 4 years to make each of the seven mirrors of the giant Magellan telescope.

“Luckily we can work on three or four at a time,” Martin said. “We have four different stations in the lab. So we can produce mirrors faster than every four years. But each one takes about four years.”

Martin takes care of polishing each mirror. They start with this coarse grinding.

“We will do another type of operation, a polishing operation, to ultimately achieve an accuracy of a millionth of an inch,” Martin said.

Right now, they are celebrating a milestone at the Mirror Lab. For the first time, they are testing one of the completed 8.4-meter mirrors on the support cells, which will hold the mirror of the giant Magellan telescope.

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“You have to have a very complex support system for one of these mirrors,” Martin said.

To ensure the mirror maintains its shape while pointing toward the stars, the support system includes 165 actuators to push and pull the back of the 12.5-ton mirror.

In the coming months, they will move the mirror and support system under the mirror lab’s test tower, to measure the mirror’s accuracy with lasers.

Currently, completed mirrors have a blue protective coating on the surface.

They are not yet mirrors. The reflective coating, only 4 millionths of an inch thick, is added on-site.

“This piece of glass that costs several million dollars and takes years to make, its purpose is to keep that layer of aluminum in the right shape,” Martin said. It’s the aluminum that does all the work. »

The seven mirrors will be shipped to Chile later this decade. The Giant Magellan Telescope is expected to be operational in the early 2030s.

“It’s a telescope bigger than anything out there and it’s going to do things that have never been done before,” Martin said.

University of Arizona and GMTO Corporation

Perhaps he could even find an illusory exoplanet, with evidence of life elsewhere in the universe.

Each of the 8.4 meter mirrors costs approximately $30 million. The budget of the Giant Magellan amounts to more than 2.5 billion dollars.

The Richard F. Caris Mirror Lab is named after a generous donor.