Vatican observatory where priests are also astrophysicists
The desert landscape in America's South West is literally awe-inspiring - the scale, the beauty and the sheer emptiness has always made humans question their place in the Universe.
That is particularly true at night when the sky, unpolluted by man-made light sources, is filled with stars.
It is no surprise, then, that the mountains in Arizona are home to many observatories where scientists from all over the world come to study the cosmos. What is less well known, is that the Vatican has long had its own observatory here too.
BBC Pop Up's Matt Danzico met two of the Jesuit priests who are also astrophysicists to find out more about this unexpected convergence of religion and science.
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