The Story of Earth Quotes

“To get a sense of the scale of Earth history, imagine walking back in time, a hundred years per step—every pace equal to more than three human generations. A mile takes you 175,000 years into the past. The twenty miles of Chesapeake cliffs, a hard day’s walk to be sure, correspond to more than 3 million years. But to make even a small dent in Earth history, you would have to keep walking at that rate for many weeks. Twenty days of effort at twenty miles a day and a hundred years per step would take you back 70 million years, to just before the mass death of the dinosaurs. Five months of twenty-mile walks would correspond to more than 530 million years, the time of the Cambrian “explosion”—the near-simultaneous emergence of myriad hard-shelled animals. But at a hundred years per footstep, you’d have to walk for almost three years to reach the dawn of life, and almost four years to arrive at Earth’s beginnings.”
― Robert M. Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“The lessons of rocks, stars,and life are clear. To understand Earth, you must divorce yourself for the inconsequential temporal or spacial scale of human life. We live on a single tiny world in a cosmos of a hundred billion galaxies, each with a hundred billion stars. Similarly, we live day by day in a cosmos aged hundreds of billions of days. If you seek meaning and purpose in the cosmos, you will not find it in any privileged moment or place tied to human existence.”
― Robert m hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“No direct evidence yet documents Earth’s tidal cycles more than a billion years ago, but we can be confident that 4.5 billion years ago things were a lot wilder. Not only did Earth have five-hour days, but the nearby Moon was much, much faster in its close orbit, as well. The Moon took only eighty-four hours—three and a half modern days—to go around Earth. With Earth spinning so fast and the Moon orbiting so fast, the familiar cycle of new Moon, waxing Moon, full Moon, and waning Moon played out in frenetic fast-forward: every few five-hour days saw a new lunar phase. Lots of consequences follow from this truth, some less benign than others. With such a big lunar obstruction in the sky and such rapid orbital motions, eclipses would have been frequent events. A total solar eclipse would have occurred every eighty-four hours at virtually every new Moon, when the Moon was positioned between Earth and the Sun. For some few minutes, sunlight would have been completely blocked, while the stars and planets suddenly popped out against a black sky, and the Moon’s fiery volcanoes and magma oceans stood out starkly red against the black lunar disk. Total lunar eclipses occurred regularly as well, almost every forty-two hours later, like clockwork. During every full Moon, when Earth lies right between the Sun and the Moon, Earth’s big shadow would have completely obscured the giant face of the bright shining Moon. Once again the stars and planets would have suddenly popped out against a black sky, as the Moon’s volcanoes put on their ruddy show. Monster tides were a far more violent consequence of the Moon’s initial proximity. Had both Earth and the Moon been perfectly rigid solid bodies, they would appear today much as they did 4.5 billion years ago: 15,000 miles apart with rapid rotational and orbital motions and frequent eclipses. But Earth and the Moon are not rigid. Their rocks can flex and bend; especially when molten, they swell and recede with the tides. The young Moon, at a distance of 15,000 miles, exerted tremendous tidal forces on Earth’s rocks, even as Earth exerted an equal and opposite gravitational force on the largely molten lunar landscape. It’s difficult to imagine the immense magma tides that resulted. Every few hours Earth’s largely molten rocky surface may have bulged a mile or more outward toward the Moon, generating tremendous internal friction, adding more heat and thus keeping the surface molten far longer than on an isolated planet. And Earth’s gravity returned the favor, bulging the Earth-facing side of the Moon outward, deforming our satellite out of perfect roundness.”
― Robert Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“Oceans today represent only about 0.02 percent of Earth’s total mass, while the atmosphere is no more than one part per million of its bulk. Nevertheless, oceans and atmosphere have exerted, and continue to exert, disproportionately large influences in making Earth the unique world that it is.”
― Robert M. Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“The same kind of situation complicates many public debates, like that over global warming. Many scientists predict that altered atmospheric conditions will raise the average global temperature by several degrees. But such changes can also cause extreme weather, which may mean worse snowstorms in the southern United States. Global warming may alter ocean currents like the Gulf Stream and ultimately turn northern Europe into a much colder Siberian-type icebox. Anomalies like this fuel the global warming naysayers: scientists say the world is getting hotter, but you’ve just suffered through the biggest snowstorm in your region’s history. How should you respond? A judicious response is that nature is amazing—rich, varied, complex, and intricately interconnected, with a messy, long history. Anomalies, whether in planetary orbits or North American weather, are not just inconvenient details to brush aside: they are the very essence of understanding what really happened—how things really work. We develop grand and general models of how nature works, and then we use the odd details to refine the original imperfect model (or if the exceptions overwhelm the rule, we regroup around a new model). That’s why good scientists revel in anomalies. If we understood everything, if we could predict everything, there’d be no point in getting up in the morning and heading to the lab.”
― Robert M. Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“According to the latest interpretations, Earth has experienced a repeated cycle of at least five supercontinent assemblies and breakups, extending back perhaps three billion years.”
― Robert M. Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“Chirality matters. In the curious case of the artificial fragrance limonene, the right-handed form smells like an orange, whereas the left-handed version of this simple ring-shaped molecule smells like a lemon. The smell receptors in your nose are sensitive to chirality, so right- and left-limonene transmit slightly different signals to your brain. Taste buds are less sensitive to the differences between right- and left-handed sugars. They both taste sweet, but our body’s fine-tuned digestive system can process only the right-handed forms. The artificial sweetener tagatose, a zero-calorie left-handed sugar substitute, exploits these properties. The tragic story of thalidomide also rests on handedness. The right-handed version of this drug alleviated morning sickness in pregnant women, but the left-handed variant that inevitably tagged along caused birth defects. Today the FDA imposes strict requirements for chirally pure drugs—regulations”
― Robert Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“Here I should issue a caveat. In origins-of-life research (and probably in most other disciplines as well), scientists gravitate to models that highlight their personal scientific specialty. Organic chemist Stanley Miller and his cohorts saw life’s origins as essentially a problem in organic chemistry. Geochemists, by contrast, have tended to focus on more intricate origins scenarios involving such variables as temperature and pressure and chemically complex rocks. Experts in membrane-forming lipid molecules promote the “lipid world,” while molecular biologists who study DNA and RNA view the “RNA world” as the model to beat. Specialists who study viruses, or metabolism, or clays, or the deep biosphere have their idiosyncratic prejudices as well. We all do it; we all focus”
― Robert Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“Astronomers using powerful telescopes have found that about two of every three stars we see in the night sky are actually binaries—systems in which two stars orbit each other in a dance about a common gravitational center.”
― Robert M. Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“Today we experience oxygen in the most intimate exchange. With every breath we take, a tiny portion of the air becomes a part of us, even as a tiny part of us becomes the air. As days pass, our bodies melt away and form again in moment-by-moment chemical reactions with oxygen. Our tissues are replaced over and over again throughout our lives, Earth’s finite store of atoms recycling among air, sea, land, and all its living forms. Most of the atoms that formed your infant body at birth are now dispersed, as your present atoms will be again, if you have the good fortune to live a few more years on this oxygen-rich planetary home.”
― Robert M. Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“Four and a half billion is a number almost beyond reckoning. The current Guinness world record for longevity is held by a French woman who lived to celebrate her 122nd birthday—so humans fall far short of living even for 4.5 billion seconds (about 144 years). All of recorded human history is much less than 4.5 billion minutes. And yet geologists claim that Earth has been around for more than 4.5 billion years.”
― Robert M. Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“Assembling Novopangaea is a tricky game. It’s easy to take today’s continental movements and predict ten or twenty million years down the road. The Atlantic will have widened by several hundred miles, while the Pacific will have shrunk by an equal amount. Australia will have moved north toward South Asia, and Antarctica will have shifted slightly away from the South Pole, also in the direction of South Asia. Africa is also on the move, inching northward to close off the Mediterranean Sea. In a few tens of millions of years, Africa will have collided with southern Europe, in the process closing up the Mediterranean and pushing up a Himalayan-size mountain range that will dwarf the Alps. So the map of the world twenty million years hence will appear familiar but skewed. Looking as far as one hundred million years into the future in this way is fairly safe, and most modelers arrive at similar geographies of a world where the Atlantic Ocean has overtaken the Pacific as the grandest body of water on Earth.”
― Robert M. Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“Clay consists primarily of ultra-fine-grained microscopic mineral bits that soak up water and form sticky, gooey masses. If you’ve ever gotten your foot or your car stuck in deep, wet clay, you won’t soon forget. A principal mode of clay mineral formation is weathering, especially weathering by chemical alteration under the wet, acidic conditions of the late Neoproterozoic.”
― Robert Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“What we call pure water at room temperature contains equal numbers of positive hydronium and negative hydroxyl groups, at a concentration that translates to a pH of 7 (a “power of hydrogen” of 10−7 moles of hydronium groups per liter, in chemistry terms).”
― Robert Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“Then something. The concept is beyond our ability to craft metaphors. Our universe did not suddenly appear where there was only vacuum before, for before the Big Bang there was no volume and no time. Our concept of nothing implies emptiness—before the Big Bang there was nothing to be empty in. Then in an instant, there was not just something, but everything that would ever be, all at once.”
― Robert Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet

“Play that cosmic tape backward, and everything converges down to a point about 13.7 billion years ago. That’s the Big Bang. The light from some of these most distant objects has been traveling through space for more than 13 billion years. The data on this point are unassailable. Any claim that Earth’s age is ten thousand years or less defies the overwhelming and unambiguous observational evidence from every branch of science.”
― Robert M. Hazen, The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet