The students of the Vatican Observatory’s biennial summer school (this year’s topic, “Stellar Variability in the Era of Large Surveys”) were received by Pope Francis in a private audience on 14 June. Introducing them, I mentioned to the Pope that along with four weeks of heavy astrophysics our school is also including special lectures to reflect on not only what we are studying, but why we study it.

“Why does the Vatican have an Observatory?” That common question begs the bigger one, “Why does anyone study astronomy?”