The line has always gotten laughs. It comes at a point in my public talks when I want to convey how comically recent is our current understanding of the universe—so recent that people who were present at the creation still walk among us. I’ve never thought my father would care that I was making a joke at his expense, sort of; I’ve always suspected, instead, that he would thrill to the association. The universe was one of his favorite things.
Chester Joseph Panek was born in Chicago in 1920, the same year that two astronomers met in Baird Auditorium at the Smithsonian Museum of Natural History and held what professional and amateur science historians have come to call the Great Debate. Harlow Shapley of the Mount Wilson Observatory contended that the vast array of stars we call the Milky Way comprises the universe in its entirety. Heber Curtis, director of the Lick Observatory, countered that at least some of the seeming smudges, or nebulae, at the farthest reaches of the most powerful telescopes lay beyond the Milky Way and were “island universes” equal in size and magnitude to our own island universe. Edwin Hubble resolved that question four years later, when he confirmed that the Andromeda nebula was an island universe—what we would call a galaxy.
That discovery marked the birth of the modern cosmos. Before Hubble, we lived in a universe that was as vast as the stars, but no vaster, and didn’t much change over time. As I once heard an astrophysicist say, “A poor soldier who died in the trenches in 1914 knew as much about the universe as a caveman.”
Me, too, before I began writing about science in the mid-1990s. Well, maybe that’s an exaggeration; I took an Astronomy course in college and wrote a paper on black holes. But in no way did I appreciate the magnitude of what we’d come to learn since the 1920s. How the scale of the cosmos had grown from one island universe to hundreds of billions of galaxies. How the history of the cosmos had shifted from eternally repetitive motions throughout space to structural evolution over time. How cosmology itself had found the facts to allow it to graduate from speculation to science—beginning with the 1965 detection of the Cosmic Microwave Background, the remnant energy from the early universe and the discovery that marked the birth of the Big Bang interpretation.
“The Scale of the Universe: Cosmology Solved?” was the subject of a follow-up Great Debate, in October 1998. It, too, took place in the Baird Auditorium of the Smithsonian Museum of Natural History. This time the main speakers were Michael Turner and P. James E. Peebles, theorists at the University of Chicago and Princeton. Their roles were to disagree about the question mark in the subtitle.
Turner argued that the question mark was hardly even necessary—that cosmologists were closing the last loopholes in the Standard Cosmological Model. They had evidence in support of the Big Bang, they had evidence that a mysterious dark matter comprises about 24 percent of the universe, and, as of earlier that year, they had evidence that the expansion of the universe is accelerating under the influence of a mysterious dark energy that comprises about 72 percent of the universe.
Peebles argued that the question mark was necessary—well, maybe not necessary, given the evidence earlier that year that the expansion of the universe is accelerating under the influence of a mysterious dark energy that comprises about 72 percent of the universe, but at least, you know, advisable. Which is to say, he had been assigned the weaker argument.
What fascinated me over the course of that Sunday afternoon in Washington, however, was the presence of Peebles himself. In 1965, he had predicted the temperature of the Cosmic Microwave Background, and that prediction was instrumental in creating the consensus among scientists as to how the universe evolved—meaning that the Big Bang interpretation of the universe is so recent that its creators still walk among us. (Also—as I saw for myself on the train trip back up the Eastern seaboard—sit among us, sipping a Bud.)
I don’t know how much my father knew about the universe back in the ’90s, when I embarked on my own education. But I do know he got a kick out of the fact that the evidence for the Cosmic Microwave Background was detected in a radio receiver. He built radios as a kid in his bedroom, he and a friend ran an Armed Forces radio station in North Africa during the War, and his team put up a string of 90-foot radio towers that turned out to be part of the communications system for the Manhattan Project. (Not that anybody knew what the Manhattan Project was. But everybody knew that if you wanted to get somewhere fast, you hitched a ride on a vehicle carrying a crate stenciled with the word “MANHATTAN,” because you’d get waved through every checkpoint.) He also got a kick out of the fact that the discovery of the Cosmic Microwave Background was made at Bell Labs, in New Jersey. My father spent his working life at Illinois Bell, and late in his career his job took him to Bell Labs on several occasions.
Whatever the state of knowledge he brought to our conversations about the universe, we wound up learning a lot together. I made sure to send him brochures or other reading material from conferences I attended, as well as my own articles and books. Even as his eyesight began to fail, he kept asking for more updates, so I sent him astronomy magazines devoted to stunning images, or my own manuscripts printed in 16-point type. Whenever a package from me arrived, he would call from Chicago to marvel at this discovery or that, and at how far our knowledge had come just within his own lifetime, and at how much we still didn’t know—like what dark matter and dark energy, together comprising 96 percent of the universe, actually are. Just last month he told me that he wished he could live long enough to see these mysteries solved—but then again, he sighed, there would always be new mysteries to solve.
My father died two weeks ago yesterday. In public, I think I’ll add a line to my talks: that my sons can say their father is older than the universe—in terms of the consensus about the Big Bang interpretation—and that their children will be able to say their fathers are older than the universe—in terms of the Standard Cosmological Model that Turner celebrated in 1998. In private, I’ll try to pass along the lessons I learned from my father, lessons that any parent would do well to pass along to a child: Keep your eyes open, question what you see, and don’t be afraid of the dark.