Lost in the cosmos

THE first page of Chet Raymo’s new book states its grand objective: “ ‘Walking Zero’ is about the epic struggle to understand cosmic space and time.” He approaches this task in signature Raymo manner -- by conceiving a modest premise that looks arbitrary, even whimsical, but turns out to be artfully composed to nurture his theme. He walks the line of zero longitude, called the prime meridian, across southeastern England. Why? Because he wants to trace humanity’s slow realization that we are not the center of the universe.

Raymo’s latest demonstration of literate science writing beautifully links these seemingly unrelated subjects. Involving far more than the struggle to measure longitude, the prime meridian embodies our growing understanding both of Earth’s place in the cosmos and of the layered strata of its past. Raymo isn’t content to tell merely the story of the meridian. The imaginary line crosses the turf where many important figures in this drama -- Isaac Newton, Charles Darwin, Pierre Teilhard de Chardin -- lived or worked. It even runs near the grave of that blustering fraud Piltdown Man. Raymo perceived the links among these topics and settings, then constructed a hike that would string them in the proper order to unfurl his story.

Until his recent retirement (he turns 70 this year), Raymo taught physics and astronomy at Stonehill College in Massachusetts. His books, although grounded in everyday life, are infused with the big-picture view of time and space these disciplines inspire. Like many writers, he elliptically orbits a cluster of themes, wandering away but finding himself drawn back by a gravitational pull he can’t resist. One favorite topic is the hubris of Homo sapiens in the face of cosmic time and distance. “Walking Zero” is the first book he has built entirely around this idea -- our gradual abandonment of the assumption that our planet is at the center of creation, our grudging admission that our souls may not be basking in the spotlight of divine attention.

Raymo has published more than a dozen books, and the older he gets the more they demonstrate another of his refrains: the aesthetic urge toward elegance and simplicity that motivates much of science. In “Walking Zero” and two previous books, “Climbing Brandon: Science and Faith on Ireland’s Holy Mountain” and “The Path,” he weds theme and approach in formats so appropriate they seem inevitable rather than constructed. “The Path,” for example, is also built around a walk -- the route he followed through decades of daily strolls to his college. Raymo fashioned the narrative as a saunter through the natural history of domesticated space in America. Each scene opens outward: from a stream to the unique chemistry of water, from a woodland to why trees stand upright and support our homes. The new book unfolds in a similar manner.

Science writers are like photographers: However much they may tinker with the final print, they begin by recording some aspect of the real world. Raymo’s landscape in “Walking Zero” is so down to earth that within these pages we can, like Dr. Johnson, kick a stone to refute Bishop Berkeley. Raymo is writing about historical personages, provable discoveries, reproducible experiments, predictable laws of nature. But he lights this factual terrain romantically, from a low angle, accenting details in scenes painstakingly composed to show a wild nature looming behind the tamed human foreground.

Two of Raymo’s heroes are the natural philosophers Eratosthenes and Aristarchus. The former measured Earth’s circumference with shadow angles; the latter dared to calculate the relative sizes (and even distance apart) of sun and Earth. The parade of remarkable individuals includes Mary Anning, a fossil collector, who, hobbled by Regency skirts, managed to climb the steep cliffs of Dorset and unearth monsters; and Johannes Kepler, who, while distilling his laws of planetary motion from mountains of data, also fought to keep his trouble-prone mother from being burned as a witch. Clearly none of these people lolled in an ivory tower.

Raymo describes a key moment in geological history as “worth savoring.” He also savors the resonant juxtaposition of image and idea. He describes the last version of John Harrison’s famous longitude clock as resembling “a miniature model for some fantasy factory cranking out interchangeable parts.” By itself this description is vivid, but the image also sets up the next sentence, which makes a second point and promotes the first to a new level: “And in a sense that is what it is, the products being interchangeable instants of time.” With his fluent synthesis of image and explanation, Raymo explores the way our sense of time -- and thus our view of ourselves -- turned from the cosmic rhythm of the heavens to the assembly-line products of the industrial era.

The book could have been longer. Part of the charm of Raymo’s writing is that he addresses large topics in small spaces. Yet “Walking Zero’s” frame is a trek across a certain portion of the planet, so it would be nice to have more texture, a better sense of the solid earth on which he plants his hiking boots as he ponders the heavens. Although there are lush panoramas of space and time, we get only quick sketches of the earth and sky that surround him and presumably inspire these thoughts.

Not that any reader will ask for less meditation. Raymo takes a voluptuous pleasure in what Virginia Woolf once described as “the strange, pleasant process called thinking.” He writes with a larger context in mind -- not transmuting every flash of quail into a metaphor, like Thoreau, but at least placing new knowledge in context and keeping an eye on its philosophical implications. Raised a Catholic in the Protestant South, Raymo abandoned organized religion’s comfortable human-centered universe while in college. In its place, he turned toward the natural stage behind the human carnival.

But he readily admits to feeling a religious thirst for meaning. He takes his walks and climbs his mountains fully prepared for a personal encounter with the universe. Raymo doesn’t divide his books into categories (hard-headed science, poetic yearning); each contains his full attention, both scientific and emotional. Several, especially “Honey From Stone” and “Climbing Brandon,” address “spiritual vertigo,” his term for our response to the dizzying magnitude of space.

Often Raymo describes scientific concepts with religious imagery. “The Sun is a typical star in a universe of uncountable stars,” he writes toward the end of “Walking Zero.” “The human abode is a dust mote in a cathedral swirling with dust motes.” In less than 200 pages, he walks us through the history of this hard-won realization: that our planet, the epicenter of our imagination and the archive of our evolution, is a minute speck in a vast universe. But he doesn’t feel diminished by the mote’s unimportance -- he feels exalted by the grandeur of the setting. Apparently it would never occur to him that our mote might be floating in a warehouse or a dustbin. In Raymo’s vision of nature, the light of many suns is angling toward us as if through stained-glass windows, and the cosmos is a sacred place. *