Across the Universe: Tides in our affairs


This column first ran in the Tablet in January, 2011

January is the month when novices from my Jesuit province go to a retreat house in Gloucester, Massachusetts, for a month of silent prayer. Surrounded by nature – the tides rolling onto the rocky shoreline, the inevitable winter blizzard – they confront God and themselves. Meanwhile, my nephews are avoiding those same winter storms by visiting their grandparents in Florida, enjoying the tides in the Gulf of Mexico. Surfing is, perhaps, its own form of prayer.

Tides along the Oregon coast

The ocean tides are a powerful symbol of God’s presence. Their regular rise and fall makes the whole Earth feel like it’s alive.

To the American political commentator, Bill O’Reilly, who strongly identifies himself with his Catholic roots, they are in fact a proof of God. Recently, debating an atheist on his television program, O’Reilly shrugged off his opponent’s arguments by merely observing: “Tide goes in, tide goes out. Never a miscommunication. You can’t explain that. You can’t explain why the tide goes in.”

O’Reilly’s comments, however, have attracted their share of scorn – most notably from another television commentator and fellow Catholic, the comedian Stephen Colbert, who suggested O’Reilly could use perhaps use a refresher course in astronomy.

Actually, understanding the ocean’s tides is far trickier than most astronomy textbooks will admit. Yes, the Moon pulls on the ocean’s water, causing it to rise, generating dramatic waves so beloved by artists and surfers. But the tides lag significantly behind the Moon. Indeed, complex interactions between water and land lead to some places – like the Gulf of Mexico – experiencing tides at remarkably irregular intervals, while other places – for example, the Mediterranean – hardly see any tides at all. And it takes some elegant mathematics to explain why there’s a second tide on the side of the Earth away from the Moon.

O’Reilly wouldn’t be the first to misunderstand tides, of course. In The Two World Systems – the book that led to his trial by the Church –  Galileo famously used the tides as evidence that the Earth spins. His argument was, in fact, ludicrously wrong. Galileo didn’t understand momentum (which Newton would only explain forty years later). And, having experienced only the Mediterranean tides, he seemed to think that there was only one tide a day.

Yet though his argument was wrong, Galileo still was right: the Earth does spin.

Twenty years after Galileo, the Jesuit astronomer Riccioli (as recently translated by the science historian [and fellow Catholic Astronomer blogger!] Christopher Graney, quoted in The New Scientist) assembled 77 scientific arguments for why the Earth couldn’t be spinning. Among them, apparently, was the first description of what would later be called the Coriolis effect, which we now know describes cyclonic weather patterns. His arguments showed great insight, and were hard to refute at the time. But of course, he was wrong: the Earth does spin.

Riccioli’s science was constrained by religious pressures, which led him to a false scientific conclusion. O’Reilly’s bad-science proof of religion is even more insidious, however. His “god of the tides” is merely one force among many forces in nature: nothing more than a pagan deity. Both Riccioli and O’Reilly were trying to defend the Church, but both were operating under false ideas about religion and science. They do inform each other; but they cannot offer each other proofs.

It’s not the existence of the tides, or their regularity, that demonstrate God’s presence. That’s precisely the part of the tides that science addresses quite well, with elaborate but beautiful mathematical formulae. What science does not even want to address is the beauty that we experience in tides. Science gives us answers about how the universe works; it doesn’t explain why we are so delighted to find those answers.

God doesn’t make the tides. He makes them awesome. We learn that from prayer; and from any surfer.

Br. Guy Consolmagno

About Br. Guy Consolmagno

Brother Guy Consolmagno SJ is Director of the the Vatican Observatory and President of the Vatican Observatory Foundation. A native of Detroit, Michigan, he earned undergraduate and masters' degrees from MIT, and a Ph. D. in Planetary Science from the University of Arizona; he was a postdoctoral research fellow at Harvard and MIT, served in the US Peace Corps (Kenya), and taught university physics at Lafayette College before entering the Jesuits in 1989.

At the Vatican Observatory since 1993, his research explores connections between meteorites, asteroids, and the evolution of small solar system bodies, observing Kuiper Belt comets with the Vatican's 1.8 meter telescope in Arizona, and applying his measure of meteorite physical properties to understanding asteroid origins and structure. Along with more than 200 scientific publications, he is the author of a number of popular books including Turn Left at Orion (with Dan Davis), and most recently Would You Baptize an Extraterrestial? (with Father Paul Mueller, SJ). He also has hosted science programs for BBC Radio 4, been interviewed in numerous documentary films, appeared on The Colbert Report, and for more than ten years he has written a monthly science column for the British Catholic magazine, The Tablet.

Dr. Consolmagno's work has taken him to every continent on Earth; for example, in 1996 he spent six weeks collecting meteorites with a NASA team on the blue ice regions of East Antarctica. He has served on the governing boards of the Meteoritical Society; the American Astronomical Society Division for Planetary Sciences (of which he was chair in 2006-2007); and IAU Commission 16 (Planets and Satellites). In 2000, the small bodies nomenclature committee of the IAU named an asteroid, 4597 Consolmagno, in recognition of his work. In 2014 he received the Carl Sagan Medal from the American Astronomical Society Division for Planetary Sciences for excellence in public communication in planetary sciences.

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Across the Universe: Tides in our affairs — 2 Comments

  1. The European Space Agency(ESA) Lisa Pathfinder in its current L1 position has been allowed to move without constraint in the time period Dec 25, 2016 to Jan 14, 2017 measuring any existing tidal affects. The existence of such and their explanation would add to our aesthetic and practical understanding of God’s creation.

  2. I’m especially taken by your observation: “Science gives us answers about how the universe works; it doesn’t explain why we are so delighted to find those answers.” Perhaps an other question that, to my experience differentiates scientists from some other disciplines, is why we take as much delight in finding that our current answers fall short, and are motivated to push on.

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