A Belgian Catholic priest mapped the expanding universe before Edwin Hubble and told Albert Einstein, at the height of his fame, that his physical intuition was wrong. This episode traces the life of the father of modern cosmology, born in Charleroi in 1894, from the artillery ballistics course where he was marked down for insubordination after pointing out a math error in the official manual, to the harsh feedback from writer Leon Bloy that convinced him to abandon concordism and stop forcing science and scripture to speak with one voice.

After earning a mathematics doctorate and being ordained in 1923, he studied with Arthur Eddington at Cambridge, Harlow Shapley at Harvard, and at MIT, becoming fluent in both theory and observation. His 1927 paper proposed an expanding universe, which Einstein rejected at the Solvay Conference. When Hubble published superior data in 1929, the priest quietly deleted his own expansion-rate calculations from the 1931 English translation. That same year he proposed the primeval atom, the seed of what Fred Hoyle mockingly named the Big Bang. The episode also covers his 1951 effort to persuade Pope Pius XII to stop citing the theory as proof of Genesis, his cosmic ray research using early computers, his decades-long defense of the cosmological constant later vindicated by dark energy, and the news of the cosmic microwave background that reached him days before his death in 1966.

• The raisin bread analogy for how space itself stretches and carries galaxies apart
• Why Einstein’s Spinoza-influenced preference for a static cosmos overrode his own equations
• Why historians once suspected censorship in the missing 1931 paragraphs
• How he used MIT’s mechanical differential analyzers to trace cosmic ray trajectories
• Why he argued the cosmological constant was a real vacuum energy driving expansion