Brian Cox on What Earthly Phenomena Reveal about the Wonders of the Solar System
By Maria Popova
“I know that I am mortal by nature and ephemeral,” ur-astronomer Ptolemy contemplated nearly two millennia ago, “but when I trace at my pleasure the windings to and fro of the heavenly bodies, I no longer touch earth with my feet. I stand in the presence of Zeus himself and take my fill of ambrosia.” But while the cosmos has fascinated humanity since the dawn of time, its mesmerism isn’t that of an abstract other but, rather, the very self-reflexive awareness that Ptolemy attested to, that intimate and inextricable link between the wonders of life here on Earth and the magic we’ve always found in our closest cosmic neighbors.
That’s precisely what modern-day science-enchanter Brian Cox explores in Wonders of the Solar System (public library) — the fantastic and illuminating book based on his BBC series of the same title celebrating the spirit of exploration, and a follow-up to his Wonders of Life and every bit as brimming with his signature blend of enthralling storytelling, scientific brilliance, and contagious conviction.
Cox begins by reminding us that preserving the spirit of exploration is both a joy and a moral obligation — especially at a time when it faces tragic threats of indifference and neglect from the very authorities whose job it is to fuel it, despite a citizenry profoundly in love with the ethos of exploration:
[The spirit of exploration] is desperately relevant, an idea so important that celebration is perhaps too weak a word. It is a plea for the spirit of the navigators of the seas and the pioneers of aviation and spaceflight to be restored and cherished; a case made to the viewer and reader that reaching for worlds beyond our grasp is an essential driver of progress and necessary sustenance for the human spirit. Curiosity is the rocket fuel that powers our civilization. If we deny this innate and powerful urge, perhaps because earthly concerns seem more worthy or pressing, then the borders of our intellectual and physical domain will shrink with our ambitions. We are part of a much wider ecosystem, and our prosperity and even long-term survival are contingent on our understanding of it.
But most revelational of all is Cox’s gift from illustrating what our Earthly phenomena, right here on our seemingly ordinary planet, reveal about the wonders and workings of the Solar System.
Tornadoes, for instance, tell us how our star system was born — the processes that drive these giant rotating storms obey the same physics forces that caused clumps to form at the center of nebulae five billion years ago, around which the gas cloud collapsed and began spinning ever-faster, ordering the chaos, until the early Solar System was churned into existence. This universal principle, known as the conservation of angular momentum, is also what drives a tornado’s destructive spiral.
This is how our Solar System was born: rather than the whole system collapsing into the Sun, a disc of dust and gas extending billions of kilometers into space formed around the new shining star. In just a few hundred million years, pieces of the cloud collapsed to form planets and moons, and so a star system, our Solar System, was formed. The journey from chaos into order had begun.
Then we have Iceland’s icebergs and glacial lagoons, which offer remarkable insight into the nature of Saturn’s rings. Both shine with puzzling brightness — the lagoons, here on Earth, by bringing pure water that is thousands of years old and free of pollutants from the bottom of the seabed to the surface as they rise, forming ice crystals of exceptional vibrance; Saturn’s rings, young and ever-changing, by circling icy ring particles around the planet, constantly crashing them together and breaking them apart, thus exposing bright new facets of ice that catch the sunlight and dazzle amidst a Solar System that is otherwise “a very dirty place.”
It’s difficult to imagine the scale, beauty and intricacy of Saturn’s rings here on Earth, but the glacial lagoons of Iceland can transport our minds across millions of kilometers of space and help us understand the true nature of the rings. … At first sight, the lagoon appears to be a solid sheet of pristine ice,but this is an illusion. The surface is constantly shifting, an almost organic, every-changing raft of thousands of individual icebergs floating on the water. The structure of Saturn’s rings is similar, because despite appearances the rings aren’t solid. Each ring is made up of hundreds of ringlets and each ringlet is made up of billions of separate pieces. Captured by Saturn’s gravity, the ring particles independently orbit the panel in an impossibly thin layer.
Chinese lanterns, it turns out, explain how Saturn’s moon Titan, Cox’s favorite wonder of the Solar System yet the one he first thought would be least interesting, keeps its atmosphere — an atmosphere more similar to Earth’s than any other solar bodies have, rendering the moon a sort of deep-frozen primordial Earth. Since the temperature of gas is just a measure of how fast the molecules are bouncing around, and since an ideal gas contestant exists, if a container has a fixed volume and rising temperature, you have to raise the pressure or lower the number of molecules in order to keep everything in balance. That’s what makes a Chinese lantern levitate, and also what allows Titan, which sits a chilling half billion kilometers away from the Sun, keep its atmosphere in place — due to the low temperature, its molecules are moving very slowly, but the distance also means its gravitational pull, and thus pressure, is very low; thus, the two forces offset each other and the atmosphere remains perfectly afloat:
If you light the fuel beneath the lantern, the air inside the lantern heats up. This means that the molecules inside start whizzing around faster and the pressure inside the lantern begins to increase. But the lantern is open at the bottom, and therefore the pressure inside the lantern must remain the same as the pressure outside. The pressures equalize by molecules of air rushing out of the bottom of the lantern and disappearing off into the atmosphere. … Because molecules are constantly rushing out of the lantern, it weighs less and less as time goes by and eventually it is light enough to float gently off into the sky.
Cox goes on to explore other such illuminating parallels, from how Alaska’s Lake Eyak illustrate the methane cycles of the universe to what Hawaii’s Big Island tells us about the forces that keep any planet alive to how the volcanic features of India’s Deccan Traps explain why Venus choked to death. He ends with T. S. Eliot’s timeless verses on the spirit of exploration and echoes Neil deGrasse Tyson’s wisdom on your ego and the cosmic perspective, concluding:
You could take the view that our exploration of the Universe has made us somehow insignificant; one tiny planet around one star amongst hundreds of billions. But I don’t take that view, because we’ve discovered that it takes the rarest combination of chance and the laws of Nature to produce a planet that can support a civilization, that most magnificent structure that allows us to explore and understand the Universe. That’s why, for me, our civilization is the wonder of the Solar System, and if you were to be looking at the Earth from outside the Solar System that much would be obvious. We have written the evidence of our existence onto the surface of our planet. Our civilization has become a beacon that identifies our planet as a home to life.
Published August 23, 2013