Vatican’s telescope in Southern Arizona charting the stars for 30 years

By Carissa Krautscheid 

Many people might be surprised that the Vatican has a direct presence in the Diocese of Tucson, at its telescope, the Vatican Advanced Technology Telescope (VATT). Others are surprised by the Catholic Church’s legacy of scientific discovery and continued contributions to the body of knowledge. 

To the Jesuit and diocesan priests and brothers who serve the Church as astronomers, it is not surprising at all. “We work among the wonders of creation, which increases our grasp of the wonder of God,” said Father Christopher Corbally, S.J., one of the Vatican astronomers residing in Tucson. “With the Jesuits, I can be both a priest and a scientist.” 

There are five Jesuit priests assigned to research and minister in the Diocese of Tucson:  

• Fr. Richard Boyle, S.J., studies star clusters in the Milky Way Galaxy 

• Fr. David Brown, S.J., specializes in stellar evolution 

• Fr. Christopher Corbally, S.J., researches stellar spectroscopy as well as human sentience 

• Fr. Paul Gabor, S.J., focuses on instrumentation and extrasolar planets 

• Fr. Jean-Baptiste Kikwaya Eluo, S.J., studies meteors, fireballs, asteroids, comets, and near-Earth objects 

Astronomers, clergy, and laity alike joined in a multi-day celebration of the VATT’s 30th anniversary. More than 100 attended a gala dinner with Vatican Observatory (VO) director, Brother Guy Consolmagno, S.J., and special guest, Major General Charles F. Bolden, Jr., retired NASA astronaut and administrator. 

The following day 50 participants traveled to Mount Graham, the sky-island near Safford, Arizona, where the VATT is perched alongside two other telescopes. Why southeastern Arizona? “Sky conditions are among the best in the world for astronomical observations,” explained the Vatican Observatory website. 


Photo credit: Paul Schulz

This telescope employs ground-breaking technology, showing that the Catholic Church remains active in scientific discovery. “Dedicated in 1993, the VATT utilizes some of the most advanced and innovative optics, electronics, and mechanics available — once again positioning the Vatican at the forefront of astronomy” (VO). 

The dedication plaque on the VATT walls reads, “This new tower for studying the stars has been erected on this peaceful site... May whoever searches here night and day the far reaches of space use it joyfully with the help of God.” 

Why is the VATT so significant?  

“The VATT has served as a testbed for a number of other revolutionary ideas for modern telescope design” (VO). It employs the “first mirror ever made using revolutionary spin-casting and polishing technologies that are now used to make giant telescopes such as the Large Binocular Telescope” built 12 years later on Mount Graham “and the Giant Magellan Telescope” which is currently under construction in Chile. “The primary mirror of the VATT was developed by the Mirror Lab at the University of Arizona and has gone on to revolutionize the creation of large, lightweight, telescope mirrors” (VO). 

Over the past 30 years, Vatican astronomers have stood “at the forefront of scientific research covering a broad range of topics, from an examination of the tiniest specks of interplanetary dust to the origin and structure of the universe” (VO).  

Scientific research conducted at the VATT includes “the search for Massive Compact Halo Objects (MACHOs) around the Andromeda Galaxy. As a result of these observations, the MACHO theory for dark matter was decisively ruled out” in addition to “characterizing the demographic and star-forming properties of over 300 nearby galaxies, … surveying open star clusters, … and discovering over a hundred new asteroids” (VO). 

“The VATT is ideally suited to the measurement of light curves. Here, sets of images are collected over a period of time (anywhere from minutes to years), to measure how different objects’ brightnesses change over time. From these light curves, it’s possible to extract information such as the size and distance of stars or the shape and physical properties of near-Earth asteroids and trans-Neptunian objects” (VO). 

But why does the Catholic Church pursue astronomy? 

“For over 440 years, the Vatican has been advancing scientific inquiry and promoting awareness of how our universe works. The Vatican Observatory is one of the oldest active astronomical observatories in the world, with its roots going back to 1582 and the Gregorian reform of the calendar. Here are a few examples of our contribution throughout the centuries: 

• Astronomy: specialized in long-term survey projects from the 19th century Map of the Heavens to modern catalogs of galaxies, open clusters, and peculiar stars. 

• Physics and planetary sciences: observatory scientists study a range of related sciences such as quantum gravity; meteorites and Moon rocks; and possible life on planets orbiting other stars. 

• Education: workshops offered include the Vatican Observatory Summer Schools (VOSS) and Astronomy for Catholic Ministers and Educators (ACME). Vatican astronomers also visit schools to elaborate on the dynamic between faith and science. 

• Culture and History: the 1582 Gregorian Calendar, biographies of notable Catholic scientists, and workshops on the peaceful uses of space all show the Observatory’s active role in the larger society and the Church.” (VO). 

Understanding creation and the universe fosters awe of the Creator. For Catholics, science and faith are not at odds. Rather, the facts of logic and science are confirmation of a higher being outside of time.  

Through the on-going research of the Vatican Observatory, the Catholic Church remains on the cutting-edge of scientific discovery and the cultivation of faith.