KGUN 9NewsAbsolutely Arizona


Why the Pope's telescope is in Southern Arizona

Posted: 2:43 PM, Dec 19, 2022
Updated: 2022-12-19 16:43:06-05
Vatican Advanced Technology Telescope

TUCSON, Ariz. (KGUN) — It might surprise you to learn that Mt. Graham, near Safford, is home to a telescope operated by the Vatican—and that Tucson is home to an official "seat of the Vatican," where those researchers live and work.

Here's the "Absolutely Arizona" story behind the pope's telescope.

"Officially I think it falls under the category of miscellaneous 'foreign government office.' So, right in Tucson, you have a miscellaneous foreign government office," said Fr. Paul Gabor, Vice Director of the Vatican Observatory.

Vatican home in Tucson

Gabor is explaining why when you step into a mid-century modern home near the U of A ,you are considered to be in a foreign government office of Vatican City.

A photo of Pope Francis on the wall might be your first clue that this is an official seat of the Vatican. A small chapel off the living room is another strong clue.

Vatican Chapel in Tucson

But why Tucson, and why the Vatican?

It's actually home to Jesuit priests, like Gabor, who are studying astronomy for the Vatican.

While they live in Tucson, and spend time doing research and teaching at the U of A, they travel to Mt. Graham to do their observations at the VATT: the Vatican Advanced Technology Telescope.

That's right, the Pope's telescope is located in Southeast Arizona.

Why here?

First, you have to understand why the Catholic Church is interested in astronomy.

"Show to the world that clergy can do science." 

That's the mission statement put forth in 1891 by Pope Leo XIII. That's also when the Vatican established an observatory to show the world how the Church supports science.

But the telescope wouldn't stay in Vatican City for long.

"This is a story of light pollution and how it persecutes poor astronomers."

In the 1930s, Pope Pius XI relocated the Observatory to Castel Gandolfo, southeast of Rome. Within a few decades, light pollution forced the Vatican to look to the dark skies of Southeast Arizona.

"In collaboration with the University of Arizona we moved here so that we could use the facilities of the university for astronomical observations."

That's how the Vatican Observatory Foundation established a presence east of Tucson on Mt. Graham. By 1993, the Vatican had a telescope of its own, thanks to the U of A's Mirror Lab and a new process of spin casting.

Vatican Advanced Technology Telescope

"We actually have the very first mirror made that way, the prototype. We got it simply because it was there and somebody needed to build a telescope around it."

$4 million later and the Vatican Observatory Foundation had the VATT on Mt. Graham, taking advantage of our near-perfect dark sky.

"We hope that not only now, but also in the future, we'll be able to conduct astronomical observations from the site here, and won't need to move somewhere else again," said Gabor.

The 72-inch telescope is about to celebrate 30 years of operation. That's three decades of clergy studying and sharing amazing photos and research data.

Gabor says the Vatican telescope on Mt. Graham is well known by astronomers, but few people in Catholic parishes know about the telescope, and the dozen Jesuit priests doing research.

Image from the Vatican Advanced Technology Telescope

Soon, the VATT will be going through a major upgrade. The telescope on Mt. Graham will be fully automated in 2024.

"It will be possible to use it for science purposes, for science cases, in the current mode of operation would be very difficult to realize," said Gabor.

Automation will allow for multiple research projects to be done each night, instead of just one, expanding the usefulness of the Vatican telescope.

A telescope with its roots at the Vatican, but that is very much "Absolutely Arizona."

Pat Parris is an anchor and reporter for KGUN 9. He is a graduate of Sabino High School where he was the 1982 high school state track champion in the 800 meters. While in high school and college, he worked part-time in the KGUN 9 newsroom. Share your story ideas and important issues with Pat by emailing or by connecting on Facebook, Twitter, and Instagram.