Bartusiak's "The Day We Found the Universe'

Every major culture produces epic tales of heroic deeds. In our culture, one of the best is the story of how we learned that we live in a galaxy containing billions of stars in a universe teeming with galaxies.

The universe revealed by modern astronomy dwarfs anything mankind ever imagined previously. When I first started reading science fiction in 1950, galactic empires had become a standard feature of the genre; a new trend-setting magazine called Galaxy appeared on the stands that August; and National Geographic featured pictures of different types of galaxies taken with the 200-inch telescope at Mount Palomar. I didn't realize, at the time, that all this galactic activity rested on a view of the universe that was only 25 years old.

Marcia Bartusiak's retelling of this epic quest focuses on the events leading up to January 1, 1925, the day when the last objections were dispelled and the scope and size of the universe opened before our minds. On that day, at the American Astronomical Society's annual meeting in Washington, a paper by Edwin Hubble presented conclusive proof that the so-called "spiral nebulae" were other galaxies located millions of light years from our own galaxy.

Galileo's suspicions

By the end of the 19th Century, we knew that we lived in a giant structure that contained colossal numbers of stars. We knew this structure was roughly disk-shaped, and we knew we were looking through the disk edgewise when we looked at the Milky Way. Astronomers had dubbed the structure the Galaxy, from the Greek root that gives us terms like "galactose intolerance."

The spiral nebulae were faint objects that resembled blurry blobs in the first telescopes. They were called "nebulae" because they appeared to be dimmer versions of the giant gas clouds, such as the nearby Orion Nebula, visible through small telescopes. Galileo had suspected the blobs might be farther and bigger than they appeared. Immanuel Kant advanced a similar idea.

But how could you tell? You can't determine the distance to stellar objects merely by looking at the sky. A small dim object may appear large and bright because it's close to us. A large bright object may look small and dim because it's a long way off.

Chains of logic

The discovery of the universe hinged, to a large extent, on the development of measuring techniques. The geometric technique called parallax got us started, but it only works out to a few hundred light years. The biggest strides in the long march across the cosmos required more sophisticated strategies, built on work that combined the careful analysis of pulsating stars with chains of logic that pushed outward, link by link.

Like the best science writers, Bartusiak doesn't just tell us what we know. She tells us how we learned it and why we think it's true.

A hard-nosed crime reporter

The discovery process was conducted by people, and Bartusiak is particularly good at sketching the foibles and virtues of the champions who carried the human mind across the light years. Edwin Hubble was an Anglophile whose pipe-smoking affectations irritated looser colleagues like Harlow Shapley. Shapley started his working life as a "hard-nosed reporter, covering crime and corruption in the Midwest" and went on to become the astronomer who gave us our first estimate of the size of the galaxy, and the first proof that we humans occupy an undistinguished site on the periphery.

Shapley's calculations estimated a galaxy 300,000 light years in diameter. Later work corrected that to about 100,000 light years. But until Shapley published his papers, astronomers had assumed our sun occupied a site near the center and thought they were being daring when they suggested the entire universe might consist of one galaxy 10,000 to 30,000 light years in diameter.

Science stars like Hubble are acknowledged in monuments like NASA's orbiting Hubble Telescope. But science is a communal effort. Only a book like this can recognize the many people who've made key contributions.

Heroic feats of patience

For example, Bartusiak revives the history of lesser-known figures like Vesto Slipher, who performed heroic feats of patience as he collected important stellar spectra; and James Keeler, of the Lick Observatory, whose photographs, during the last decade of the 19th Century, captured details of the spiral nebulae and placed their existence at the center of astronomy. Bartusiak's sketches of important personalities include the wealthy patrons who financed America's biggest telescopes as well as the fund-raising astronomer, George Ellery Hale, who talked the donors out of their money.

A female computer

Bartusiak's chapter devoted to Henrietta Leavitt treats her story with touching restraint, with no hint of polemic. Leavitt was one of the female "computers" who worked at the Harvard Observatories. Men theorized while women toiled at the intellectual needlework, analyzing photographic plates and working complicated equations. Leavitt, assigned to work on the Magellanic Clouds, became fascinated by variable stars and developed the theory that transformed the stars called Cepheid Variables into a measuring stick that played a pivotal role in the quest.

Had she lived a few more years, Leavitt probably would have been a candidate for a Nobel. Instead, her boss returned her to routine work he considered important, and she died prematurely of stomach cancer.

Should we be humbled or proud?

For many people, our modern picture of the universe presents a frightening image that reduces human beings to inconsequential flickers in a cold immensity. Moralistic writers like to remind us that we've been "dethroned" from our egotistical place at the center of the universe and should feel properly humbled.

But for me, the central reality of this story is the fact that a bunch of slightly comic, semi-rational primates, living on an obscure world in a dusty arm of an average spiral galaxy, managed to overcome all the obstacles set in their way and discover the true nature of their habitat. To paraphrase Sophocles: Wonders are many— and there is nothing more wondrous than the creatures who do the wondering.